[FFmpeg-devel] [PATCH v11 1/2] libavformat: add DVD-Video demuxer, powered by libdvdnav and libdvdread

Marth64 marth64 at proxyid.net
Fri Feb 9 21:30:35 EET 2024


Addresses the last round of feedback.
Fingers crossed.

- Resolves maintainability concern
- Some more formatting nits
- Removes the YUV-RGB lookup table

Signed-off-by: Marth64 <marth64 at proxyid.net>
---
 Changelog                 |    2 +
 configure                 |    8 +
 doc/demuxers.texi         |  130 ++++
 libavformat/Makefile      |    1 +
 libavformat/allformats.c  |    1 +
 libavformat/dvdvideodec.c | 1422 +++++++++++++++++++++++++++++++++++++
 6 files changed, 1564 insertions(+)
 create mode 100644 libavformat/dvdvideodec.c

diff --git a/Changelog b/Changelog
index c5fb21d198..88653bc6d3 100644
--- a/Changelog
+++ b/Changelog
@@ -24,6 +24,8 @@ version <next>:
 - ffmpeg CLI options may now be used as -/opt <path>, which is equivalent
   to -opt <contents of file <path>>
 - showinfo bitstream filter
+- DVD-Video demuxer, powered by libdvdnav and libdvdread
+
 
 version 6.1:
 - libaribcaption decoder
diff --git a/configure b/configure
index f72533b7d2..831b9f6cb6 100755
--- a/configure
+++ b/configure
@@ -227,6 +227,8 @@ External library support:
   --enable-libdavs2        enable AVS2 decoding via libdavs2 [no]
   --enable-libdc1394       enable IIDC-1394 grabbing using libdc1394
                            and libraw1394 [no]
+  --enable-libdvdnav       enable libdvdnav, needed for DVD demuxing [no]
+  --enable-libdvdread      enable libdvdread, needed for DVD demuxing [no]
   --enable-libfdk-aac      enable AAC de/encoding via libfdk-aac [no]
   --enable-libflite        enable flite (voice synthesis) support via libflite [no]
   --enable-libfontconfig   enable libfontconfig, useful for drawtext filter [no]
@@ -1806,6 +1808,8 @@ EXTERNAL_LIBRARY_GPL_LIST="
     frei0r
     libcdio
     libdavs2
+    libdvdnav
+    libdvdread
     librubberband
     libvidstab
     libx264
@@ -3523,6 +3527,8 @@ dts_demuxer_select="dca_parser"
 dtshd_demuxer_select="dca_parser"
 dv_demuxer_select="dvprofile"
 dv_muxer_select="dvprofile"
+dvdvideo_demuxer_select="mpegps_demuxer"
+dvdvideo_demuxer_deps="libdvdnav libdvdread"
 dxa_demuxer_select="riffdec"
 eac3_demuxer_select="ac3_parser"
 evc_demuxer_select="evc_frame_merge_bsf evc_parser"
@@ -6771,6 +6777,8 @@ enabled libdav1d          && require_pkg_config libdav1d "dav1d >= 0.5.0" "dav1d
 enabled libdavs2          && require_pkg_config libdavs2 "davs2 >= 1.6.0" davs2.h davs2_decoder_open
 enabled libdc1394         && require_pkg_config libdc1394 libdc1394-2 dc1394/dc1394.h dc1394_new
 enabled libdrm            && check_pkg_config libdrm libdrm xf86drm.h drmGetVersion
+enabled libdvdnav         && require_pkg_config libdvdnav "dvdnav >= 6.1.1" dvdnav/dvdnav.h dvdnav_open2
+enabled libdvdread        && require_pkg_config libdvdread "dvdread >= 6.1.2" dvdread/dvd_reader.h DVDOpen2 -ldvdread
 enabled libfdk_aac        && { check_pkg_config libfdk_aac fdk-aac "fdk-aac/aacenc_lib.h" aacEncOpen ||
                                { require libfdk_aac fdk-aac/aacenc_lib.h aacEncOpen -lfdk-aac &&
                                  warn "using libfdk without pkg-config"; } }
diff --git a/doc/demuxers.texi b/doc/demuxers.texi
index e4c5b560a6..062ea2ea42 100644
--- a/doc/demuxers.texi
+++ b/doc/demuxers.texi
@@ -285,6 +285,136 @@ This demuxer accepts the following option:
 
 @end table
 
+ at section dvdvideo
+
+DVD-Video demuxer, powered by libdvdnav and libdvdread.
+
+Can directly ingest DVD titles, specifically sequential PGCs,
+into a conversion pipeline. Menus and seeking are not supported at this time.
+
+Block devices (DVD drives), ISO files, and directory structures are accepted.
+Activate with @code{-f dvdvideo} in front of one of these inputs.
+
+Underlying playback is handled by libdvdnav, and structure parsing by libdvdread.
+FFmpeg must be built with GPL library support available as well as the
+configure switches @code{--enable-libdvdnav} and @code{--enable-libdvdread}.
+
+You will need to provide either the desired "title number" or exact PGC/PG coordinates.
+Many open-source DVD players and tools can aid in providing this information.
+If not specified, the demuxer will default to title 1 which works for many discs.
+However, due to the flexibility of the format, it is recommended to check manually.
+There are many discs that are authored strangely or with invalid headers.
+
+If the input is a real DVD drive, please note that there are some drives which may
+silently fail on reading bad sectors from the disc, returning random bits instead
+which is effectively corrupt data. This is especially prominent on aging or rotting discs.
+A second pass and integrity checks would be needed to detect the corruption.
+This is not an FFmpeg issue.
+
+ at subsection Background
+
+DVD-Video is not a directly accessible, linear container format in the
+traditional sense. Instead, it allows for complex and programmatic playback of
+carefully muxed MPEG-PS streams that are stored in headerless VOB files.
+To the end-user, these streams are known simply as "titles", but the actual
+logical playback sequence is defined by one or more "PGCs", or Program Group Chains,
+within the title. The PGC is in turn comprised of multiple "PGs", or Programs",
+which are the actual video segments (and for a typical video feature, sequentially
+ordered). The PGC structure, along with stream layout and metadata, are stored in
+IFO files that need to be parsed. PGCs can be thought of as playlists in easier terms.
+
+An actual DVD player relies on user GUI interaction via menus and an internal VM
+to drive the direction of demuxing. Generally, the user would either navigate (via menus)
+or automatically be redirected to the PGC of their choice. During this process and
+the subsequent playback, the DVD player's internal VM also maintains a state and
+executes instructions that can create jumps to different sectors during playback.
+This is why libdvdnav is involved, as a linear read of the MPEG-PS blobs on the
+disc (VOBs) is not enough to produce the right sequence in many cases.
+
+There are many other DVD structures (a long subject) that will not be discussed here.
+NAV packets, in particular, are handled by this demuxer to build accurate timing
+but not emitted as a stream. For a good high-level understanding, refer to:
+ at url{https://code.videolan.org/videolan/libdvdnav/-/blob/master/doc/dvd_structures}
+
+ at subsection Options
+
+This demuxer accepts the following options:
+
+ at table @option
+
+ at item title @var{int}
+The title number to play. Must be set if @option{pgc} and @option{pg} are not set.
+Default is 0 (auto), which currently only selects the first available title (title 1)
+and notifies the user about the implications.
+
+ at item chapter_start @var{int}
+The chapter, or PTT (part-of-title), number to start at. Default is 1.
+
+ at item chapter_end @var{int}
+The chapter, or PTT (part-of-title), number to end at. Default is 0,
+which is a special value to signal end at the last possible chapter.
+
+ at item angle @var{int}
+The video angle number, referring to what is essentially an additional
+video stream that is composed from alternate frames interleaved in the VOBs.
+Default is 1.
+
+ at item region @var{int}
+The region code to use for playback. Some discs may use this to default playback
+at a particular angle in different regions. This option will not affect the region code
+of a real DVD drive, if used as an input. Default is 0, "world".
+
+ at item pgc @var{int}
+The entry PGC to start playback, in conjunction with @option{pg}.
+Alternative to setting @option{title}.
+Chapter markers are not supported at this time.
+Default is 0, automatically resolve from value of @option{title}.
+
+ at item pg @var{int}
+The entry PG to start playback, in conjunction with @option{pgc}.
+Alternative to setting @option{title}.
+Chapter markers are not supported at this time.
+Default is 0, automatically resolve from value of @option{title}.
+
+ at item preindex @var{bool}
+Enable this to have accurate chapter (PTT) markers and duration measurement,
+which requires a slow second pass read in order to index the chapter marker
+timestamps from NAV packets. This is non-ideal extra work for real optical drives.
+It is recommended and faster to use this option with a backup of the DVD structure
+stored on a hard drive. Not compatible with @option{pgc} and @option{pg}.
+Default is 0, false.
+
+ at item trim @var{bool}
+Skip padding cells (i.e. cells shorter than 1 second) from the beginning.
+There exist many discs with filler segments at the beginning of the PGC,
+often with junk data intended for controlling a real DVD player's
+buffering speed and with no other material data value.
+Default is 1, true.
+
+ at end table
+
+ at subsection Examples
+
+ at itemize
+ at item
+Open title 3 from a given DVD structure:
+ at example
+ffmpeg -f dvdvideo -title 3 -i <path to DVD> ...
+ at end example
+
+ at item
+Open chapters 3-6 from title 1 from a given DVD structure:
+ at example
+ffmpeg -f dvdvideo -chapter_start 3 -chapter_end 6 -title 1 -i <path to DVD> ...
+ at end example
+
+ at item
+Open only chapter 5 from title 1 from a given DVD structure:
+ at example
+ffmpeg -f dvdvideo -chapter_start 5 -chapter_end 5 -title 1 -i <path to DVD> ...
+ at end example
+ at end itemize
+
 @section ea
 
 Electronic Arts Multimedia format demuxer.
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 05b9b8a115..df69734877 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -192,6 +192,7 @@ OBJS-$(CONFIG_DTS_MUXER)                 += rawenc.o
 OBJS-$(CONFIG_DV_MUXER)                  += dvenc.o
 OBJS-$(CONFIG_DVBSUB_DEMUXER)            += dvbsub.o rawdec.o
 OBJS-$(CONFIG_DVBTXT_DEMUXER)            += dvbtxt.o rawdec.o
+OBJS-$(CONFIG_DVDVIDEO_DEMUXER)          += dvdvideodec.o
 OBJS-$(CONFIG_DXA_DEMUXER)               += dxa.o
 OBJS-$(CONFIG_EA_CDATA_DEMUXER)          += eacdata.o
 OBJS-$(CONFIG_EA_DEMUXER)                += electronicarts.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index b04b43cab3..3e905c23f8 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -150,6 +150,7 @@ extern const AVInputFormat  ff_dv_demuxer;
 extern const FFOutputFormat ff_dv_muxer;
 extern const AVInputFormat  ff_dvbsub_demuxer;
 extern const AVInputFormat  ff_dvbtxt_demuxer;
+extern const AVInputFormat  ff_dvdvideo_demuxer;
 extern const AVInputFormat  ff_dxa_demuxer;
 extern const AVInputFormat  ff_ea_demuxer;
 extern const AVInputFormat  ff_ea_cdata_demuxer;
diff --git a/libavformat/dvdvideodec.c b/libavformat/dvdvideodec.c
new file mode 100644
index 0000000000..f389afedb6
--- /dev/null
+++ b/libavformat/dvdvideodec.c
@@ -0,0 +1,1422 @@
+/*
+ * DVD-Video demuxer, powered by libdvdnav and libdvdread
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * See doc/demuxers.texi for a high-level overview.
+ *
+ * The tactical approach is as follows:
+ * 1) Open the volume with dvdread
+ * 2) Analyze the user-requested title and PGC coordinates in the IFO structures
+ * 3) Request playback at the coordinates and chosen angle with dvdnav
+ * 5) Begin the playback (reading and demuxing) of MPEG-PS blocks
+ * 6) End playback if navigation goes backwards, to a menu, or a different PGC or angle
+ * 7) Close the dvdnav VM, and free dvdread's IFO structures
+ */
+
+#include <dvdnav/dvdnav.h>
+#include <dvdread/dvd_reader.h>
+#include <dvdread/ifo_read.h>
+#include <dvdread/ifo_types.h>
+#include <dvdread/nav_read.h>
+
+#include "libavcodec/avcodec.h"
+#include "libavutil/avstring.h"
+#include "libavutil/avutil.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/mem.h"
+#include "libavutil/opt.h"
+#include "libavutil/samplefmt.h"
+#include "libavutil/time.h"
+#include "libavutil/timestamp.h"
+
+#include "avformat.h"
+#include "avio_internal.h"
+#include "avlanguage.h"
+#include "demux.h"
+#include "internal.h"
+#include "url.h"
+
+#define DVDVIDEO_MAX_PS_SEARCH_BLOCKS                   128
+#define DVDVIDEO_BLOCK_SIZE                             2048
+#define DVDVIDEO_TIME_BASE_Q                            (AVRational) { 1, 90000 }
+#define DVDVIDEO_PTS_WRAP_BITS                          64 /* VOBUs use 32 (PES allows 33) */
+
+#define DVDVIDEO_LIBDVDX_LOG_BUFFER_SIZE                1024
+
+enum DVDVideoSubpictureViewport {
+    DVDVIDEO_SUBP_VIEWPORT_FULLSCREEN,
+    DVDVIDEO_SUBP_VIEWPORT_WIDESCREEN,
+    DVDVIDEO_SUBP_VIEWPORT_LETTERBOX,
+    DVDVIDEO_SUBP_VIEWPORT_PANSCAN
+};
+static const char dvdvideo_subp_viewport_labels[4][13] = {
+    "Fullscreen", "Widescreen", "Letterbox", "Pan and Scan"
+};
+
+typedef struct DVDVideoVTSVideoStreamEntry {
+    int                                 startcode;
+    enum AVCodecID                      codec_id;
+    int                                 width;
+    int                                 height;
+    AVRational                          dar;
+    AVRational                          framerate;
+    int                                 has_cc;
+} DVDVideoVTSVideoStreamEntry;
+
+typedef struct DVDVideoPGCAudioStreamEntry {
+    int                                 startcode;
+    enum AVCodecID                      codec_id;
+    int                                 sample_fmt;
+    int                                 sample_rate;
+    int                                 bit_depth;
+    int                                 nb_channels;
+    AVChannelLayout                     ch_layout;
+    int                                 disposition;
+    const char                          *lang_iso;
+} DVDVideoPGCAudioStreamEntry;
+
+typedef struct DVDVideoPGCSubtitleStreamEntry {
+    int                                 startcode;
+    enum DVDVideoSubpictureViewport     viewport;
+    int                                 disposition;
+    const char                          *lang_iso;
+} DVDVideoPGCSubtitleStreamEntry;
+
+typedef struct DVDVideoPlaybackState {
+    int                         celln;              /* ID of the active cell */
+    int                         entry_pgn;          /* ID of the PG we are starting in */
+    int                         in_pgc;             /* if our navigator is in the PGC */
+    int                         in_ps;              /* if our navigator is in the program stream */
+    int                         in_vts;             /* if our navigator is in the VTS */
+    int64_t                     nav_pts;            /* PTS according to IFO, not frame-accurate */
+    int                         nb_cells_played;    /* number of cells played back so far */
+    uint64_t                    pgc_duration_est;   /* estimated duration as reported by IFO */
+    uint64_t                    pgc_elapsed;        /* the elapsed time of the PGC, cell-relative */
+    int                         pgc_nb_pg_est;      /* number of PGs as reported by IFOs */
+    int                         pgcn;               /* ID of the PGC we are playing */
+    int                         pgn;                /* ID of the PG we are in now */
+    int                         ptt;                /* ID of the chapter we are in now */
+    int64_t                     ts_offset;          /* PTS discontinuity offset (ex. VOB change) */
+    uint32_t                    vobu_duration;      /* duration of the current VOBU */
+    uint32_t                    vobu_e_ptm;         /* end PTS of the current VOBU */
+    int                         vtsn;               /* ID of the active VTS (video title set) */
+    uint64_t                    *pgc_pg_times_est;  /* PG start times as reported by IFO */
+    pgc_t                       *pgc;               /* handle to the active PGC */
+    dvdnav_t                    *dvdnav;            /* handle to libdvdnav */
+} DVDVideoPlaybackState;
+
+typedef struct DVDVideoDemuxContext {
+    const AVClass               *class;
+
+    /* options */
+    int                         opt_angle;          /* the user-provided angle number (1-indexed) */
+    int                         opt_chapter_end;    /* the user-provided exit PTT (0 for last) */
+    int                         opt_chapter_start;  /* the user-provided entry PTT (1-indexed) */
+    int                         opt_pg;             /* the user-provided PG number (1-indexed) */
+    int                         opt_pgc;            /* the user-provided PGC number (1-indexed) */
+    int                         opt_preindex;       /* pre-indexing mode (2-pass read) */
+    int                         opt_region;         /* the user-provided region digit */
+    int                         opt_title;          /* the user-provided title number (1-indexed) */
+    int                         opt_trim;           /* trim padding cells at beginning */
+
+    /* subdemux */
+    const AVInputFormat         *mpeg_fmt;          /* inner MPEG-PS (VOB) demuxer */
+    AVFormatContext             *mpeg_ctx;          /* context for inner demuxer */
+    uint8_t                     *mpeg_buf;          /* buffer for inner demuxer */
+    FFIOContext                 mpeg_pb;            /* buffer context for inner demuxer */
+
+    /* volume */
+    dvd_reader_t                *dvdread;           /* handle to libdvdread */
+    ifo_handle_t                *vmg_ifo;           /* handle to the VMG (VIDEO_TS.IFO) */
+    ifo_handle_t                *vts_ifo;           /* handle to the active VTS (VTS_nn_n.IFO) */
+
+    /* playback control */
+    int64_t                     first_pts;          /* the starting PTS offset of the PGC */
+    uint64_t                    duration_ptm;       /* total duration in DVD MPEG timebase */
+    int                         play_end;           /* signal EOF to the parent demuxer */
+    DVDVideoPlaybackState       play_state;         /* the active playback state */
+    int                         play_started;       /* signal that playback has started */
+    int                         segment_started;    /* signal that subdemuxer is on a segment */
+} DVDVideoDemuxContext;
+
+static void dvdvideo_libdvdread_log(void *opaque, dvd_logger_level_t level,
+                                    const char *msg, va_list msg_va)
+{
+    AVFormatContext *s = opaque;
+    char msg_buf[DVDVIDEO_LIBDVDX_LOG_BUFFER_SIZE];
+    int lavu_level = AV_LOG_DEBUG;
+
+    vsnprintf(msg_buf, sizeof(msg_buf), msg, msg_va);
+
+    if (level == DVD_LOGGER_LEVEL_ERROR)
+        lavu_level = AV_LOG_ERROR;
+    else if (level == DVD_LOGGER_LEVEL_WARN)
+        lavu_level = AV_LOG_WARNING;
+
+    av_log(s, lavu_level, "libdvdread: %s\n", msg_buf);
+}
+
+static void dvdvideo_libdvdnav_log(void *opaque, dvdnav_logger_level_t level,
+                                   const char *msg, va_list msg_va)
+{
+    AVFormatContext *s = opaque;
+    char msg_buf[DVDVIDEO_LIBDVDX_LOG_BUFFER_SIZE];
+    int lavu_level = AV_LOG_DEBUG;
+
+    vsnprintf(msg_buf, sizeof(msg_buf), msg, msg_va);
+
+    if (level == DVDNAV_LOGGER_LEVEL_ERROR)
+        lavu_level = AV_LOG_ERROR;
+    /* some discs have invalid language codes set for menus, which throws noisy warnings */
+    else if (level == DVDNAV_LOGGER_LEVEL_WARN && !av_strstart(msg, "Language", NULL))
+        lavu_level = AV_LOG_WARNING;
+
+    av_log(s, lavu_level, "libdvdnav: %s\n", msg_buf);
+}
+
+static void dvdvideo_ifo_close(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    if (c->vts_ifo)
+        ifoClose(c->vts_ifo);
+
+    if (c->vmg_ifo)
+        ifoClose(c->vmg_ifo);
+
+    if (c->dvdread)
+        DVDClose(c->dvdread);
+}
+
+static int dvdvideo_ifo_open(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    dvd_logger_cb dvdread_log_cb;
+    title_info_t title_info;
+
+    dvdread_log_cb = (dvd_logger_cb) { .pf_log = dvdvideo_libdvdread_log };
+    c->dvdread = DVDOpen2(s, &dvdread_log_cb, s->url);
+
+    if (!c->dvdread) {
+        av_log(s, AV_LOG_ERROR, "Unable to open the DVD-Video structure\n");
+
+        return AVERROR_EXTERNAL;
+    }
+
+    if (!(c->vmg_ifo = ifoOpen(c->dvdread, 0))) {
+        av_log(s, AV_LOG_ERROR, "Unable to open the VMG (VIDEO_TS.IFO)\n");
+
+        return AVERROR_EXTERNAL;
+    }
+
+    if (c->opt_title > c->vmg_ifo->tt_srpt->nr_of_srpts) {
+        av_log(s, AV_LOG_ERROR, "Title %d not found\n", c->opt_title);
+
+        return AVERROR_STREAM_NOT_FOUND;
+    }
+
+    title_info = c->vmg_ifo->tt_srpt->title[c->opt_title - 1];
+    if (c->opt_angle > title_info.nr_of_angles) {
+        av_log(s, AV_LOG_ERROR, "Angle %d not found\n", c->opt_angle);
+
+        return AVERROR_STREAM_NOT_FOUND;
+    }
+
+    if (title_info.nr_of_ptts < 1) {
+        av_log(s, AV_LOG_ERROR, "Title %d has invalid headers (no PTTs found)\n", c->opt_title);
+
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (c->opt_chapter_start > title_info.nr_of_ptts ||
+       (c->opt_chapter_end > 0 && c->opt_chapter_end > title_info.nr_of_ptts)) {
+        av_log(s, AV_LOG_ERROR, "Chapter (PTT) range [%d, %d] is invalid\n",
+                                c->opt_chapter_start, c->opt_chapter_end);
+
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (!(c->vts_ifo = ifoOpen(c->dvdread, title_info.title_set_nr))) {
+        av_log(s, AV_LOG_ERROR, "Unable to process IFO structure for VTS %d\n",
+                                title_info.title_set_nr);
+
+        return AVERROR_EXTERNAL;
+    }
+
+    if (title_info.vts_ttn < 1                                      ||
+        title_info.vts_ttn > 99                                     ||
+        title_info.vts_ttn > c->vts_ifo->vts_ptt_srpt->nr_of_srpts  ||
+        c->vts_ifo->vtsi_mat->nr_of_vts_audio_streams > 8           ||
+        c->vts_ifo->vtsi_mat->nr_of_vts_subp_streams > 32) {
+
+        av_log(s, AV_LOG_ERROR, "Title %d has invalid headers in VTS\n", c->opt_title);
+        return AVERROR_INVALIDDATA;
+    }
+
+    return 0;
+}
+
+static int dvdvideo_is_cell_promising(AVFormatContext *s, pgc_t *pgc, int celln)
+{
+    dvd_time_t cell_duration = pgc->cell_playback[celln - 1].playback_time;
+
+    return cell_duration.second >= 1 || cell_duration.minute >= 1 || cell_duration.hour >= 1;
+}
+
+static int dvdvideo_is_pgc_promising(AVFormatContext *s, pgc_t *pgc)
+{
+    for (int i = 1; i <= pgc->nr_of_cells; i++)
+        if (dvdvideo_is_cell_promising(s, pgc, i))
+            return 1;
+
+    return 0;
+}
+
+static void dvdvideo_play_close(AVFormatContext *s, DVDVideoPlaybackState *state)
+{
+    if (!state->dvdnav)
+        return;
+
+    /* not allocated by av_malloc() */
+    if (state->pgc_pg_times_est)
+        free(state->pgc_pg_times_est);
+
+    if (dvdnav_close(state->dvdnav) != DVDNAV_STATUS_OK)
+        av_log(s, AV_LOG_ERROR, "Unable to close dvdnav successfully, dvdnav error: %s\n",
+                                dvdnav_err_to_string(state->dvdnav));
+}
+
+static int dvdvideo_play_open(AVFormatContext *s, DVDVideoPlaybackState *state)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    dvdnav_logger_cb dvdnav_log_cb;
+    dvdnav_status_t dvdnav_open_status;
+    int32_t disc_region_mask;
+    int32_t player_region_mask;
+    int cur_title, cur_pgcn, cur_pgn;
+    pgc_t *pgc;
+
+    dvdnav_log_cb = (dvdnav_logger_cb) { .pf_log = dvdvideo_libdvdnav_log };
+    dvdnav_open_status = dvdnav_open2(&state->dvdnav, s, &dvdnav_log_cb, s->url);
+
+    if (!state->dvdnav                                                          ||
+        dvdnav_open_status != DVDNAV_STATUS_OK                                  ||
+        dvdnav_set_readahead_flag(state->dvdnav, 0) != DVDNAV_STATUS_OK         ||
+        dvdnav_set_PGC_positioning_flag(state->dvdnav, 1) != DVDNAV_STATUS_OK   ||
+        dvdnav_get_region_mask(state->dvdnav, &disc_region_mask) != DVDNAV_STATUS_OK) {
+
+        av_log(s, AV_LOG_ERROR, "Unable to open the DVD for playback\n");
+        goto end_dvdnav_error;
+    }
+
+    player_region_mask = c->opt_region > 0 ? (1 << (c->opt_region - 1)) : disc_region_mask;
+    if (dvdnav_set_region_mask(state->dvdnav, player_region_mask) != DVDNAV_STATUS_OK) {
+        av_log(s, AV_LOG_ERROR, "Unable to set the playback region code %d\n", c->opt_region);
+
+        goto end_dvdnav_error;
+    }
+
+    if (c->opt_pgc > 0 && c->opt_pg > 0) {
+        if (dvdnav_program_play(state->dvdnav, c->opt_title, c->opt_pgc, c->opt_pg) != DVDNAV_STATUS_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to start playback at title %d, PGC %d, PG %d\n",
+                                    c->opt_title, c->opt_pgc, c->opt_pg);
+
+            goto end_dvdnav_error;
+        }
+
+        state->pgcn = c->opt_pgc;
+        state->entry_pgn = c->opt_pg;
+    } else {
+        if (dvdnav_part_play(state->dvdnav, c->opt_title, c->opt_chapter_start) != DVDNAV_STATUS_OK ||
+            dvdnav_current_title_program(state->dvdnav, &cur_title, &cur_pgcn, &cur_pgn) != DVDNAV_STATUS_OK) {
+
+            av_log(s, AV_LOG_ERROR, "Unable to start playback at title %d, chapter (PTT) %d\n",
+                                    c->opt_title, c->opt_chapter_start);
+            goto end_dvdnav_error;
+        }
+
+        state->pgcn = cur_pgcn;
+        state->entry_pgn = cur_pgn;
+    }
+
+    pgc = c->vts_ifo->vts_pgcit->pgci_srp[state->pgcn - 1].pgc;
+
+    if (pgc->pg_playback_mode != 0) {
+        av_log(s, AV_LOG_ERROR, "Non-sequential PGCs, such as shuffles, are not supported\n");
+
+        return AVERROR_PATCHWELCOME;
+    }
+
+    if (c->opt_trim && !dvdvideo_is_pgc_promising(s, pgc)) {
+        av_log(s, AV_LOG_ERROR, "Title %d, PGC %d looks empty (may consist of padding cells), "
+                                "if you want to try anyway, disable the -trim option\n",
+                                c->opt_title, state->pgcn);
+
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (dvdnav_angle_change(state->dvdnav, c->opt_angle) != DVDNAV_STATUS_OK) {
+        av_log(s, AV_LOG_ERROR, "Unable to start playback at angle %d\n", c->opt_angle);
+
+        goto end_dvdnav_error;
+    }
+
+    /* dvdnav_describe_title_chapters() performs several validations on the title structure */
+    /* take advantage of this side effect to increase chances of a safe navigation path */
+    state->pgc_nb_pg_est = dvdnav_describe_title_chapters(state->dvdnav, c->opt_title,
+                                                          &state->pgc_pg_times_est,
+                                                          &state->pgc_duration_est);
+
+    /* dvdnav returning 0 PGs is documented as an error condition */
+    if (!state->pgc_nb_pg_est) {
+        av_log(s, AV_LOG_ERROR, "Unable to read chapter information for title %d\n", c->opt_title);
+
+        goto end_dvdnav_error;
+    }
+
+    state->nav_pts = dvdnav_get_current_time(state->dvdnav);
+    state->vtsn = c->vmg_ifo->tt_srpt->title[c->opt_title - 1].title_set_nr;
+    state->pgc = pgc;
+
+    return 0;
+
+end_dvdnav_error:
+    if (state->dvdnav)
+        av_log(s, AV_LOG_ERROR, "dvdnav error: %s\n", dvdnav_err_to_string(state->dvdnav));
+    else
+        av_log(s, AV_LOG_ERROR, "dvdnav could not be initialized\n");
+
+    return AVERROR_EXTERNAL;
+}
+
+static int dvdvideo_play_next_ps_block(AVFormatContext *s, DVDVideoPlaybackState *state,
+                                       uint8_t *buf, int buf_size,
+                                       int *p_nav_event,
+                                       void (*flush_cb)(AVFormatContext *s))
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    uint8_t nav_buf[DVDVIDEO_BLOCK_SIZE] = {0};
+    int nav_event;
+    int nav_len;
+
+    dvdnav_vts_change_event_t *e_vts;
+    dvdnav_cell_change_event_t *e_cell;
+    int cur_title, cur_pgcn, cur_pgn, cur_angle, cur_title_unused, cur_ptt, cur_nb_angles;
+    int is_cell_promising = 0;
+    pci_t *e_pci;
+    dsi_t *e_dsi;
+
+    if (buf_size != DVDVIDEO_BLOCK_SIZE) {
+        av_log(s, AV_LOG_ERROR, "Invalid buffer size (expected=%d actual=%d)\n",
+                                DVDVIDEO_BLOCK_SIZE, buf_size);
+
+        return AVERROR(EINVAL);
+    }
+
+    for (int i = 0; i < DVDVIDEO_MAX_PS_SEARCH_BLOCKS; i++) {
+        if (ff_check_interrupt(&s->interrupt_callback))
+            return AVERROR_EXIT;
+
+        if (dvdnav_get_next_block(state->dvdnav, nav_buf, &nav_event, &nav_len) != DVDNAV_STATUS_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to read next block of PGC\n");
+
+            goto end_dvdnav_error;
+        }
+
+        /* some discs follow NOPs with a premature stop event */
+        if (nav_event == DVDNAV_STOP)
+            return AVERROR_EOF;
+
+        if (nav_len > DVDVIDEO_BLOCK_SIZE) {
+            av_log(s, AV_LOG_ERROR, "Invalid block size (expected<=%d actual=%d)\n",
+                                    DVDVIDEO_BLOCK_SIZE, nav_len);
+
+            return AVERROR_INVALIDDATA;
+        }
+
+        if (dvdnav_current_title_info(state->dvdnav, &cur_title, &cur_ptt) != DVDNAV_STATUS_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to determine current title coordinates\n");
+
+            goto end_dvdnav_error;
+        }
+
+        /* we somehow navigated to a menu */
+        if (cur_title == 0 || !dvdnav_is_domain_vts(state->dvdnav))
+            return AVERROR_EOF;
+
+        if (dvdnav_current_title_program(state->dvdnav, &cur_title_unused, &cur_pgcn, &cur_pgn) != DVDNAV_STATUS_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to determine current PGC coordinates\n");
+
+            goto end_dvdnav_error;
+        }
+
+        /* we somehow left the PGC */
+        if (state->in_pgc && cur_pgcn != state->pgcn)
+            return AVERROR_EOF;
+
+        if (dvdnav_get_angle_info(state->dvdnav, &cur_angle, &cur_nb_angles) != DVDNAV_STATUS_OK) {
+            av_log(s, AV_LOG_ERROR, "Unable to determine current video angle\n");
+
+            goto end_dvdnav_error;
+        }
+
+        av_log(s, nav_event == DVDNAV_BLOCK_OK ? AV_LOG_TRACE : AV_LOG_DEBUG,
+               "new block: i=%d nav_event=%d nav_len=%d cur_title=%d "
+               "cur_ptt=%d cur_angle=%d cur_celln=%d cur_pgcn=%d cur_pgn=%d "
+               "play_in_vts=%d play_in_pgc=%d play_in_ps=%d\n",
+               i, nav_event, nav_len, cur_title,
+               cur_ptt, cur_angle, state->celln, cur_pgcn, cur_pgn,
+               state->in_vts, state->in_pgc, state->in_ps);
+
+        switch (nav_event) {
+            case DVDNAV_VTS_CHANGE:
+                if (state->in_vts)
+                    return AVERROR_EOF;
+
+                e_vts = (dvdnav_vts_change_event_t *) nav_buf;
+
+                if (e_vts->new_vtsN == state->vtsn && e_vts->new_domain == DVD_DOMAIN_VTSTitle)
+                    state->in_vts = 1;
+
+                continue;
+            case DVDNAV_CELL_CHANGE:
+                if (!state->in_vts)
+                    continue;
+
+                e_cell = (dvdnav_cell_change_event_t *) nav_buf;
+                is_cell_promising = !c->opt_trim || dvdvideo_is_cell_promising(s, state->pgc, e_cell->cellN);
+
+                av_log(s, AV_LOG_DEBUG, "new cell: prev=%d new=%d promising=%d\n",
+                                        state->celln, e_cell->cellN, is_cell_promising);
+
+                if (!state->in_ps && !state->in_pgc) {
+                    if (cur_title == c->opt_title       &&
+                        cur_ptt == c->opt_chapter_start &&
+                        cur_pgcn == state->pgcn         &&
+                        cur_pgn == state->entry_pgn     &&
+                        is_cell_promising) {
+                        state->in_pgc = 1;
+                    }
+
+                    if (c->opt_trim && !is_cell_promising)
+                        av_log(s, AV_LOG_INFO, "Skipping padding cell #%d\n", e_cell->cellN);
+                } else if (state->celln >= e_cell->cellN || state->pgn > cur_pgn) {
+                    return AVERROR_EOF;
+                }
+
+                state->celln = e_cell->cellN;
+                state->ptt = cur_ptt;
+                state->pgn = cur_pgn;
+                state->nb_cells_played++;
+
+                continue;
+            case DVDNAV_NAV_PACKET:
+                if (!state->in_pgc)
+                    continue;
+
+                if ((state->ptt > 0 && state->ptt > cur_ptt) ||
+                    (c->opt_chapter_end > 0 && cur_ptt > c->opt_chapter_end)) {
+                    return AVERROR_EOF;
+                }
+
+                e_pci = dvdnav_get_current_nav_pci(state->dvdnav);
+                e_dsi = dvdnav_get_current_nav_dsi(state->dvdnav);
+
+                if (e_pci == NULL || e_dsi == NULL ||
+                    e_pci->pci_gi.vobu_s_ptm > e_pci->pci_gi.vobu_e_ptm) {
+
+                    av_log(s, AV_LOG_ERROR, "Invalid NAV packet\n");
+                    return AVERROR_INVALIDDATA;
+                }
+
+                state->vobu_duration = e_pci->pci_gi.vobu_e_ptm - e_pci->pci_gi.vobu_s_ptm;
+                state->pgc_elapsed += state->vobu_duration;
+                state->nav_pts = dvdnav_get_current_time(state->dvdnav);
+                state->ptt = cur_ptt;
+                state->pgn = cur_pgn;
+
+                av_log(s, AV_LOG_DEBUG,
+                       "NAV pack: s_ptm=%d e_ptm=%d "
+                       "scr=%d lbn=%d vobu_duration=%d nav_pts=%ld\n",
+                       e_pci->pci_gi.vobu_s_ptm, e_pci->pci_gi.vobu_e_ptm,
+                       e_dsi->dsi_gi.nv_pck_scr,
+                       e_pci->pci_gi.nv_pck_lbn, state->vobu_duration, state->nav_pts);
+
+                if (!state->in_ps) {
+                    av_log(s, AV_LOG_DEBUG, "navigation: locked to program stream\n");
+
+                    state->in_ps = 1;
+                } else {
+                    if (state->vobu_e_ptm != e_pci->pci_gi.vobu_s_ptm) {
+                        if (flush_cb)
+                            flush_cb(s);
+
+                        state->ts_offset += state->vobu_e_ptm - e_pci->pci_gi.vobu_s_ptm;
+                    }
+                }
+
+                state->vobu_e_ptm = e_pci->pci_gi.vobu_e_ptm;
+
+                (*p_nav_event) = nav_event;
+
+                return nav_len;
+            case DVDNAV_BLOCK_OK:
+                if (!state->in_ps) {
+                    if (state->in_pgc)
+                        i = 0; /* necessary in case we are skipping junk cells at the beginning */
+                    continue;
+                }
+
+                if (nav_len != DVDVIDEO_BLOCK_SIZE) {
+                    av_log(s, AV_LOG_ERROR, "Invalid MPEG block size (expected=%d actual=%d)\n",
+                                            DVDVIDEO_BLOCK_SIZE, nav_len);
+
+                    return AVERROR_INVALIDDATA;
+                }
+
+                if (cur_angle != c->opt_angle) {
+                    av_log(s, AV_LOG_ERROR, "Unexpected angle change (expected=%d new=%d)\n",
+                                            c->opt_angle, cur_angle);
+
+                    return AVERROR_INPUT_CHANGED;
+                }
+
+                memcpy(buf, &nav_buf, nav_len);
+
+                /* in case NAV packet is missed */
+                state->ptt = cur_ptt;
+                state->pgn = cur_pgn;
+
+                (*p_nav_event) = nav_event;
+
+                return nav_len;
+            case DVDNAV_STILL_FRAME:
+            case DVDNAV_WAIT:
+            case DVDNAV_HOP_CHANNEL:
+            case DVDNAV_HIGHLIGHT:
+                if (state->in_ps)
+                    return AVERROR_EOF;
+
+                if (nav_event == DVDNAV_STILL_FRAME) {
+                    if (dvdnav_still_skip(state->dvdnav) != DVDNAV_STATUS_OK) {
+                        av_log(s, AV_LOG_ERROR, "Unable to skip still image\n");
+
+                        goto end_dvdnav_error;
+                    }
+                }
+
+                if (nav_event == DVDNAV_WAIT) {
+                    if (dvdnav_wait_skip(state->dvdnav) != DVDNAV_STATUS_OK) {
+                        av_log(s, AV_LOG_ERROR, "Unable to skip WAIT event\n");
+
+                        goto end_dvdnav_error;
+                    }
+                }
+
+                continue;
+            case DVDNAV_STOP:
+                return AVERROR_EOF;
+            default:
+                continue;
+        }
+    }
+
+    av_log(s, AV_LOG_ERROR, "Unable to find next program stream block\n");
+
+    return AVERROR_INVALIDDATA;
+
+end_dvdnav_error:
+    av_log(s, AV_LOG_ERROR, "dvdnav error (title=%d pgc=%d pg=%d cell=%d): %s\n",
+                            cur_title, cur_pgcn, cur_pgn, state->celln,
+                            dvdnav_err_to_string(state->dvdnav));
+
+    return AVERROR_EXTERNAL;
+}
+
+static int dvdvideo_pgc_preindex(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0, interrupt = 0;
+    int nb_chapters = 0, last_ptt = c->opt_chapter_start;
+    uint64_t cur_chapter_offset = 0, cur_chapter_duration = 0;
+    DVDVideoPlaybackState state = {0};
+
+    uint8_t nav_buf[DVDVIDEO_BLOCK_SIZE];
+    int nav_event;
+
+    if (c->opt_chapter_start == c->opt_chapter_end)
+        return ret;
+
+    av_log(s, AV_LOG_INFO,
+           "Indexing chapter markers, this will take a long time. Please wait...\n");
+
+    if ((ret = dvdvideo_play_open(s, &state)) < 0 || state.pgc->nr_of_programs == 1)
+        return ret;
+
+    while (!(interrupt = ff_check_interrupt(&s->interrupt_callback))) {
+        ret = dvdvideo_play_next_ps_block(s, &state, nav_buf, DVDVIDEO_BLOCK_SIZE,
+                                          &nav_event, NULL);
+        if (ret < 0 && ret != AVERROR_EOF)
+            goto end_close;
+
+        if (nav_event != DVDNAV_NAV_PACKET && ret != AVERROR_EOF)
+            continue;
+
+        if (state.ptt == last_ptt) {
+            cur_chapter_duration += state.vobu_duration;
+            /* ensure we add the last chapter */
+            if (ret != AVERROR_EOF)
+                continue;
+        }
+
+        if (!avpriv_new_chapter(s, nb_chapters, DVDVIDEO_TIME_BASE_Q, cur_chapter_offset,
+                                cur_chapter_offset + cur_chapter_duration, NULL)) {
+            ret = AVERROR(ENOMEM);
+            goto end_close;
+        }
+
+        nb_chapters++;
+        cur_chapter_offset += cur_chapter_duration;
+        cur_chapter_duration = state.vobu_duration;
+        last_ptt = state.ptt;
+
+        if (ret == AVERROR_EOF)
+            break;
+    }
+
+    if (interrupt) {
+        ret = AVERROR_EXIT;
+        goto end_close;
+    }
+
+    if (ret < 0 && ret != AVERROR_EOF)
+        goto end_close;
+
+    s->duration = av_rescale_q(state.pgc_elapsed, DVDVIDEO_TIME_BASE_Q, AV_TIME_BASE_Q);
+    c->duration_ptm = state.pgc_elapsed;
+
+    av_log(s, AV_LOG_INFO, "Chapter marker indexing complete\n");
+    ret = 0;
+
+end_close:
+    dvdvideo_play_close(s, &state);
+
+    return ret;
+}
+
+static int dvdvideo_pgc_chapters_setup(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    uint64_t time_prev = 0;
+    int64_t total_duration = 0;
+
+    int chapter_start = c->opt_chapter_start - 1;
+    int chapter_end = c->opt_chapter_end > 0 ? c->opt_chapter_end : c->play_state.pgc_nb_pg_est - 1;
+
+    if (chapter_start == chapter_end || c->play_state.pgc_nb_pg_est == 1) {
+        s->duration = av_rescale_q(c->play_state.pgc_duration_est,
+                                   DVDVIDEO_TIME_BASE_Q, AV_TIME_BASE_Q);
+        return 0;
+    }
+
+    for (int i = chapter_start; i < chapter_end; i++) {
+        uint64_t time_effective = c->play_state.pgc_pg_times_est[i] - c->play_state.nav_pts;
+
+        if (!avpriv_new_chapter(s, i, DVDVIDEO_TIME_BASE_Q, time_prev, time_effective, NULL))
+            return AVERROR(ENOMEM);
+
+        time_prev = time_effective;
+        total_duration = time_effective;
+    }
+
+    if (c->opt_chapter_start == 1 && c->opt_chapter_end == 0)
+        s->duration = av_rescale_q(c->play_state.pgc_duration_est,
+                                   DVDVIDEO_TIME_BASE_Q, AV_TIME_BASE_Q);
+    else
+        s->duration = av_rescale_q(total_duration,
+                                   DVDVIDEO_TIME_BASE_Q, AV_TIME_BASE_Q);
+
+    return 0;
+}
+
+static int dvdvideo_video_stream_analyze(AVFormatContext *s, video_attr_t video_attr,
+                                         DVDVideoVTSVideoStreamEntry *entry)
+{
+    AVRational framerate;
+    int height = 0;
+    int width = 0;
+    int is_pal = video_attr.video_format == 1;
+
+    framerate = is_pal ? (AVRational) { 25, 1 } : (AVRational) { 30000, 1001 };
+    height = is_pal ? 576 : 480;
+
+    if (height > 0) {
+        switch (video_attr.picture_size) {
+            case 0: /* D1 */
+                width = 720;
+                break;
+            case 1: /* 4CIF */
+                width = 704;
+                break;
+            case 2: /* Half D1 */
+                width = 352;
+                break;
+            case 3: /* CIF */
+                width = 352;
+                height /= 2;
+                break;
+        }
+    }
+
+    if (!width || !height) {
+        av_log(s, AV_LOG_ERROR, "Invalid video stream parameters in the IFO headers, "
+                                "this could be an authoring error or empty title "
+                                "(video_format=%d picture_size=%d)\n",
+                                video_attr.video_format, video_attr.picture_size);
+
+        return AVERROR_INVALIDDATA;
+    }
+
+    entry->startcode = 0x1E0;
+    entry->codec_id = !video_attr.mpeg_version ? AV_CODEC_ID_MPEG1VIDEO : AV_CODEC_ID_MPEG2VIDEO;
+    entry->width = width;
+    entry->height = height;
+    entry->dar = video_attr.display_aspect_ratio ? (AVRational) { 16, 9 } : (AVRational) { 4, 3 };
+    entry->framerate = framerate;
+    entry->has_cc = !is_pal && (video_attr.line21_cc_1 || video_attr.line21_cc_2);
+
+    return 0;
+}
+
+static int dvdvideo_video_stream_add(AVFormatContext *s,
+                                     DVDVideoVTSVideoStreamEntry *entry,
+                                     enum AVStreamParseType need_parsing)
+{
+    AVStream *st;
+    FFStream *sti;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->id = entry->startcode;
+    st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
+    st->codecpar->codec_id = entry->codec_id;
+    st->codecpar->width = entry->width;
+    st->codecpar->height = entry->height;
+    st->codecpar->format = AV_PIX_FMT_YUV420P;
+    st->codecpar->color_range = AVCOL_RANGE_MPEG;
+
+    st->codecpar->framerate = entry->framerate;
+#if FF_API_R_FRAME_RATE
+    st->r_frame_rate = entry->framerate;
+#endif
+    st->avg_frame_rate = entry->framerate;
+
+    sti = ffstream(st);
+    sti->request_probe = 0;
+    sti->need_parsing = need_parsing;
+    sti->display_aspect_ratio = entry->dar;
+    sti->avctx->framerate = entry->framerate;
+
+    if (entry->has_cc)
+        sti->avctx->properties |= FF_CODEC_PROPERTY_CLOSED_CAPTIONS;
+
+    avpriv_set_pts_info(st, DVDVIDEO_PTS_WRAP_BITS,
+                        DVDVIDEO_TIME_BASE_Q.num, DVDVIDEO_TIME_BASE_Q.den);
+
+    return 0;
+}
+
+static int dvdvideo_video_stream_setup(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+    DVDVideoVTSVideoStreamEntry entry = {0};
+
+    if ((ret = dvdvideo_video_stream_analyze(s, c->vts_ifo->vtsi_mat->vts_video_attr, &entry)) < 0 ||
+        (ret = dvdvideo_video_stream_add(s, &entry, AVSTREAM_PARSE_HEADERS)) < 0) {
+
+        av_log(s, AV_LOG_ERROR, "Unable to add video stream\n");
+        return ret;
+    }
+
+    return ret;
+}
+
+static int dvdvideo_audio_stream_analyze(AVFormatContext *s, audio_attr_t audio_attr,
+                                         uint16_t audio_control, DVDVideoPGCAudioStreamEntry *entry)
+{
+    int startcode = 0;
+    enum AVCodecID codec_id = AV_CODEC_ID_NONE;
+    int sample_fmt = AV_SAMPLE_FMT_NONE;
+    int sample_rate = 0;
+    int bit_depth = 0;
+    int nb_channels = 0;
+    AVChannelLayout ch_layout = (AVChannelLayout) {0};
+    char lang_dvd[3] = {0};
+
+    int position = (audio_control & 0x7F00) >> 8;
+
+    /* XXX(PATCHWELCOME): SDDS is not supported due to lack of sample material */
+    switch (audio_attr.audio_format) {
+        case 0: /* AC3 */
+            codec_id = AV_CODEC_ID_AC3;
+            sample_fmt = AV_SAMPLE_FMT_FLTP;
+            sample_rate = 48000;
+            startcode = 0x80 + position;
+            break;
+        case 2: /* MP1 */
+            codec_id = AV_CODEC_ID_MP1;
+            sample_fmt = audio_attr.quantization ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
+            sample_rate = 48000;
+            bit_depth = audio_attr.quantization ? 20 : 16;
+            startcode = 0x1C0 + position;
+            break;
+        case 3: /* MP2 */
+            codec_id = AV_CODEC_ID_MP2;
+            sample_fmt = audio_attr.quantization ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
+            sample_rate = 48000;
+            bit_depth = audio_attr.quantization ? 20 : 16;
+            startcode = 0x1C0 + position;
+            break;
+        case 4: /* DVD PCM */
+            codec_id = AV_CODEC_ID_PCM_DVD;
+            sample_fmt = audio_attr.quantization ? AV_SAMPLE_FMT_S32 : AV_SAMPLE_FMT_S16;
+            sample_rate = audio_attr.sample_frequency ? 96000 : 48000;
+            bit_depth = audio_attr.quantization == 2 ? 24 : (audio_attr.quantization ? 20 : 16);
+            startcode = 0xA0 + position;
+            break;
+        case 6: /* DCA */
+            codec_id = AV_CODEC_ID_DTS;
+            sample_fmt = AV_SAMPLE_FMT_FLTP;
+            sample_rate = 48000;
+            bit_depth = audio_attr.quantization == 2 ? 24 : (audio_attr.quantization ? 20 : 16);
+            startcode = 0x88 + position;
+            break;
+    }
+
+    nb_channels = audio_attr.channels + 1;
+
+    if (codec_id == AV_CODEC_ID_NONE     ||
+        startcode == 0                   ||
+        sample_fmt == AV_SAMPLE_FMT_NONE ||
+        sample_rate == 0                 ||
+        nb_channels == 0) {
+
+        av_log(s, AV_LOG_ERROR, "Invalid audio stream parameters in the IFO headers, "
+                                "this could be an authoring error or dummy title "
+                                "(stream position %d in IFO)\n", position);
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (nb_channels == 2)
+        ch_layout = (AVChannelLayout) AV_CHANNEL_LAYOUT_STEREO;
+    else if (nb_channels == 6)
+        ch_layout = (AVChannelLayout) AV_CHANNEL_LAYOUT_5POINT1;
+    else if (nb_channels == 7)
+        ch_layout = (AVChannelLayout) AV_CHANNEL_LAYOUT_6POINT1;
+    else if (nb_channels == 8)
+        ch_layout = (AVChannelLayout) AV_CHANNEL_LAYOUT_7POINT1;
+
+
+    if (audio_attr.application_mode == 1) {
+        entry->disposition |= AV_DISPOSITION_KARAOKE;
+
+        av_log(s, AV_LOG_WARNING, "Extended karaoke metadata is not supported at this time "
+                                  "(stream id=%d)\n", startcode);
+    }
+
+    if (audio_attr.code_extension == 2)
+        entry->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
+    if (audio_attr.code_extension == 3 || audio_attr.code_extension == 4)
+        entry->disposition |= AV_DISPOSITION_COMMENT;
+
+    AV_WB16(lang_dvd, audio_attr.lang_code);
+
+    entry->startcode = startcode;
+    entry->codec_id = codec_id;
+    entry->sample_rate = sample_rate;
+    entry->bit_depth = bit_depth;
+    entry->nb_channels = nb_channels;
+    entry->ch_layout = ch_layout;
+    entry->lang_iso = ff_convert_lang_to(lang_dvd, AV_LANG_ISO639_2_BIBL);
+
+    return 0;
+}
+
+static int dvdvideo_audio_stream_add(AVFormatContext *s, DVDVideoPGCAudioStreamEntry *entry,
+                                     enum AVStreamParseType need_parsing)
+{
+    AVStream *st;
+    FFStream *sti;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->id = entry->startcode;
+    st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
+    st->codecpar->codec_id = entry->codec_id;
+    st->codecpar->format = entry->sample_fmt;
+    st->codecpar->sample_rate = entry->sample_rate;
+    st->codecpar->bits_per_coded_sample = entry->bit_depth;
+    st->codecpar->bits_per_raw_sample = entry->bit_depth;
+    st->codecpar->ch_layout = entry->ch_layout;
+    st->codecpar->ch_layout.nb_channels = entry->nb_channels;
+    st->disposition = entry->disposition;
+
+    if (entry->lang_iso)
+        av_dict_set(&st->metadata, "language", entry->lang_iso, 0);
+
+    sti = ffstream(st);
+    sti->request_probe = 0;
+    sti->need_parsing = need_parsing;
+
+    avpriv_set_pts_info(st, DVDVIDEO_PTS_WRAP_BITS,
+                        DVDVIDEO_TIME_BASE_Q.num, DVDVIDEO_TIME_BASE_Q.den);
+
+    return 0;
+}
+
+static int dvdvideo_audio_stream_add_all(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+
+    for (int i = 0; i < c->vts_ifo->vtsi_mat->nr_of_vts_audio_streams; i++) {
+        DVDVideoPGCAudioStreamEntry entry = {0};
+
+        if (!(c->play_state.pgc->audio_control[i] & 0x8000))
+            continue;
+
+        if ((ret = dvdvideo_audio_stream_analyze(s, c->vts_ifo->vtsi_mat->vts_audio_attr[i],
+                                                 c->play_state.pgc->audio_control[i], &entry)) < 0)
+            goto break_error;
+
+        /* IFO structures can declare duplicate entries for the same startcode */
+        for (int j = 0; j < s->nb_streams; j++)
+            if (s->streams[j]->id == entry.startcode)
+                continue;
+
+        if ((ret = dvdvideo_audio_stream_add(s, &entry, AVSTREAM_PARSE_HEADERS)) < 0)
+            goto break_error;
+
+        continue;
+
+break_error:
+        av_log(s, AV_LOG_ERROR, "Unable to add audio stream at position %d\n", i);
+        return ret;
+    }
+
+    return ret;
+}
+
+static int dvdvideo_subp_stream_analyze(AVFormatContext *s, uint32_t offset, subp_attr_t subp_attr,
+                                        DVDVideoPGCSubtitleStreamEntry *entry)
+{
+    char lang_dvd[3] = {0};
+
+    entry->startcode = 0x20 + (offset & 0x1F);
+
+    if (subp_attr.lang_extension == 9)
+        entry->disposition |= AV_DISPOSITION_FORCED;
+
+    AV_WB16(lang_dvd, subp_attr.lang_code);
+    entry->lang_iso = ff_convert_lang_to(lang_dvd, AV_LANG_ISO639_2_BIBL);
+
+    return 0;
+}
+
+static int dvdvideo_subp_stream_add(AVFormatContext *s, DVDVideoPGCSubtitleStreamEntry *entry,
+                                    enum AVStreamParseType need_parsing)
+{
+    AVStream *st;
+    FFStream *sti;
+    int ret = 0;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->id = entry->startcode;
+    st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
+    st->codecpar->codec_id = AV_CODEC_ID_DVD_SUBTITLE;
+
+    if (entry->lang_iso)
+        av_dict_set(&st->metadata, "language", entry->lang_iso, 0);
+
+    av_dict_set(&st->metadata, "VIEWPORT", dvdvideo_subp_viewport_labels[entry->viewport], 0);
+
+    st->disposition = entry->disposition;
+
+    sti = ffstream(st);
+    sti->request_probe = 0;
+    sti->need_parsing = need_parsing;
+
+    avpriv_set_pts_info(st, DVDVIDEO_PTS_WRAP_BITS,
+                        DVDVIDEO_TIME_BASE_Q.num, DVDVIDEO_TIME_BASE_Q.den);
+
+    return ret;
+}
+
+static int dvdvideo_subp_stream_add_internal(AVFormatContext *s, uint32_t offset,
+                                             subp_attr_t subp_attr,
+                                             enum DVDVideoSubpictureViewport viewport)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+    DVDVideoPGCSubtitleStreamEntry entry = {0};
+
+    entry.viewport = viewport;
+
+    if ((ret = dvdvideo_subp_stream_analyze(s, offset, subp_attr, &entry)) < 0)
+        goto end_error;
+
+    /* IFO structures can declare duplicate entries for the same startcode */
+    for (int i = 0; i < s->nb_streams; i++)
+        if (s->streams[i]->id == entry.startcode)
+            goto end;
+
+    if ((ret = dvdvideo_subp_stream_add(s, &entry, AVSTREAM_PARSE_HEADERS)) < 0)
+        goto end_error;
+
+    goto end;
+
+end_error:
+    av_log(s, AV_LOG_ERROR, "Unable to add subtitle stream\n");
+
+end:
+    return ret;
+}
+
+static int dvdvideo_subp_stream_add_all(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    if (!c->vts_ifo->vtsi_mat->nr_of_vts_subp_streams)
+        return 0;
+
+    for (int i = 0; i < c->vts_ifo->vtsi_mat->nr_of_vts_subp_streams; i++) {
+        int ret = 0;
+        uint32_t subp_control;
+        subp_attr_t subp_attr;
+        video_attr_t video_attr;
+
+        subp_control = c->play_state.pgc->subp_control[i];
+        if (!(subp_control & 0x80000000))
+            continue;
+
+        /* there can be several presentations for one SPU */
+        /* the DAR check is flexible in order to support weird authoring */
+        video_attr = c->vts_ifo->vtsi_mat->vts_video_attr;
+        subp_attr = c->vts_ifo->vtsi_mat->vts_subp_attr[i];
+
+        /* 4:3 */
+        if (!video_attr.display_aspect_ratio) {
+            if ((ret = dvdvideo_subp_stream_add_internal(s, subp_control >> 24, subp_attr,
+                                                         DVDVIDEO_SUBP_VIEWPORT_FULLSCREEN)) < 0)
+                return ret;
+
+            continue;
+        }
+
+        /* 16:9 */
+        if ((    ret = dvdvideo_subp_stream_add_internal(s, subp_control >> 16, subp_attr,
+                                                         DVDVIDEO_SUBP_VIEWPORT_WIDESCREEN)) < 0)
+            return ret;
+
+        /* 16:9 letterbox */
+        if (video_attr.permitted_df == 2 || video_attr.permitted_df == 0)
+            if ((ret = dvdvideo_subp_stream_add_internal(s, subp_control >> 8, subp_attr,
+                                                         DVDVIDEO_SUBP_VIEWPORT_LETTERBOX)) < 0)
+                return ret;
+
+        /* 16:9 pan-and-scan */
+        if (video_attr.permitted_df == 1 || video_attr.permitted_df == 0)
+            if ((ret = dvdvideo_subp_stream_add_internal(s, subp_control, subp_attr,
+                                                         DVDVIDEO_SUBP_VIEWPORT_PANSCAN)) < 0)
+                return ret;
+    }
+
+    return 0;
+}
+
+static void dvdvideo_subdemux_flush(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    if (!c->segment_started)
+        return;
+
+    av_log(s, AV_LOG_DEBUG, "flushing sub-demuxer\n");
+    avio_flush(&c->mpeg_pb.pub);
+    ff_read_frame_flush(c->mpeg_ctx);
+    c->segment_started = 0;
+}
+
+static int dvdvideo_subdemux_read_data(void *opaque, uint8_t *buf, int buf_size)
+{
+    AVFormatContext *s = opaque;
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+    int nav_event;
+
+    if (c->play_end)
+        return AVERROR_EOF;
+
+    ret = dvdvideo_play_next_ps_block(opaque, &c->play_state, buf, buf_size,
+                                      &nav_event, dvdvideo_subdemux_flush);
+
+    if (ret == AVERROR_EOF) {
+        c->mpeg_pb.pub.eof_reached = 1;
+        c->play_end = 1;
+
+        return AVERROR_EOF;
+    }
+
+    if (ret >= 0 && nav_event == DVDNAV_NAV_PACKET)
+        return FFERROR_REDO;
+
+    return ret;
+}
+
+static void dvdvideo_subdemux_close(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    av_freep(&c->mpeg_pb.pub.buffer);
+    av_freep(&c->mpeg_pb);
+    avformat_close_input(&c->mpeg_ctx);
+}
+
+static int dvdvideo_subdemux_open(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+
+    if (!(c->mpeg_fmt = av_find_input_format("mpeg")))
+        return AVERROR_DEMUXER_NOT_FOUND;
+
+    if (!(c->mpeg_ctx = avformat_alloc_context()))
+        return AVERROR(ENOMEM);
+
+    if (!(c->mpeg_buf = av_mallocz(DVDVIDEO_BLOCK_SIZE))) {
+        avformat_free_context(c->mpeg_ctx);
+        c->mpeg_ctx = NULL;
+
+        return AVERROR(ENOMEM);
+    }
+
+    ffio_init_context(&c->mpeg_pb, c->mpeg_buf, DVDVIDEO_BLOCK_SIZE, 0, s,
+                      dvdvideo_subdemux_read_data, NULL, NULL);
+    c->mpeg_pb.pub.seekable = 0;
+
+    if ((ret = ff_copy_whiteblacklists(c->mpeg_ctx, s)) < 0) {
+        avformat_free_context(c->mpeg_ctx);
+        c->mpeg_ctx = NULL;
+
+        return ret;
+    }
+
+    c->mpeg_ctx->flags = AVFMT_FLAG_CUSTOM_IO | AVFMT_FLAG_GENPTS;
+    c->mpeg_ctx->ctx_flags |= AVFMTCTX_UNSEEKABLE;
+    c->mpeg_ctx->probesize = 0;
+    c->mpeg_ctx->max_analyze_duration = 0;
+    c->mpeg_ctx->interrupt_callback = s->interrupt_callback;
+    c->mpeg_ctx->pb = &c->mpeg_pb.pub;
+    c->mpeg_ctx->io_open = NULL;
+
+    return avformat_open_input(&c->mpeg_ctx, "", c->mpeg_fmt, NULL);
+}
+
+static int dvdvideo_read_header(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret = 0;
+
+    if (c->opt_title == 0) {
+        av_log(s, AV_LOG_INFO, "Defaulting to title #1. "
+                               "This is not always the main feature, validation suggested.\n");
+
+        c->opt_title = 1;
+    }
+
+    if (c->opt_pgc) {
+        if (c->opt_pg == 0)
+            av_log(s, AV_LOG_ERROR, "Invalid coordinates. If -pgc is set, -pg must be set too.\n");
+        else if (c->opt_chapter_start > 1 || c->opt_chapter_end > 0 || c->opt_preindex)
+            av_log(s, AV_LOG_ERROR, "-pgc is not compatible with the -preindex or "
+                                    "-chapter_start/-chapter_end options\n");
+
+        return AVERROR(EINVAL);
+    }
+
+    if ((ret = dvdvideo_ifo_open(s)) < 0)
+        return ret;
+
+    if (c->opt_preindex && (ret = dvdvideo_pgc_preindex(s)) < 0)
+        return ret;
+
+    if ((ret = dvdvideo_play_open(s, &c->play_state)) < 0   ||
+        (ret = dvdvideo_subdemux_open(s)) < 0               ||
+        (ret = dvdvideo_video_stream_setup(s)) < 0          ||
+        (ret = dvdvideo_audio_stream_add_all(s)) < 0        ||
+        (ret = dvdvideo_subp_stream_add_all(s)) < 0)
+        return ret;
+
+    if (!c->opt_preindex)
+        return dvdvideo_pgc_chapters_setup(s);
+
+    return ret;
+}
+
+static int dvdvideo_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    int ret;
+    enum AVMediaType st_type;
+    int found_stream = 0;
+    int64_t cur_delta = 0;
+
+    if (c->play_end)
+        return AVERROR_EOF;
+
+    ret = av_read_frame(c->mpeg_ctx, pkt);
+
+    if (ret < 0)
+        return ret;
+
+    if (!c->segment_started)
+        c->segment_started = 1;
+
+    /* map the subdemuxer stream to the parent subdemuxer's stream (by startcode) */
+    st_type = c->mpeg_ctx->streams[pkt->stream_index]->codecpar->codec_type;
+    for (int i = 0; i < s->nb_streams; i++) {
+        if (s->streams[i]->id == c->mpeg_ctx->streams[pkt->stream_index]->id) {
+            pkt->stream_index = s->streams[i]->index;
+            found_stream = 1;
+            break;
+        }
+    }
+
+    if (!found_stream) {
+        av_log(s, AV_LOG_DEBUG, "discarding frame with stream that was not in IFO headers "
+                                "(stream id=%d)\n", c->mpeg_ctx->streams[pkt->stream_index]->id);
+
+        return FFERROR_REDO;
+    }
+
+    if (!c->play_started) {
+        if (st_type != AVMEDIA_TYPE_VIDEO || pkt->pts == AV_NOPTS_VALUE ||
+                                             pkt->dts == AV_NOPTS_VALUE ||
+                                             !(pkt->flags & AV_PKT_FLAG_KEY)) {
+            av_log(s, AV_LOG_VERBOSE, "discarding packet which is not a video keyframe or "
+                                      "with unset PTS/DTS at start\n");
+            return FFERROR_REDO;
+        }
+
+        c->first_pts = pkt->pts;
+        c->play_started = 1;
+
+        pkt->pts = 0;
+        pkt->dts = c->play_state.ts_offset - pkt->pts;
+    } else {
+        cur_delta = c->play_state.ts_offset - c->first_pts;
+
+        if (c->play_state.nb_cells_played == 1 && (pkt->pts == AV_NOPTS_VALUE ||
+                                                   pkt->dts == AV_NOPTS_VALUE ||
+                                                   (pkt->pts + cur_delta) < 0)) {
+            av_log(s, AV_LOG_VERBOSE, "discarding packet with negative PTS or unset PTS/DTS "
+                                      "(this is OK at the start of the first playback cell)\n");
+            return FFERROR_REDO;
+        }
+
+        if (pkt->pts != AV_NOPTS_VALUE)
+            pkt->pts += cur_delta;
+        if (pkt->dts != AV_NOPTS_VALUE)
+            pkt->dts += cur_delta;
+    }
+
+    av_log(s, AV_LOG_TRACE, "st=%d pts=%ld dts=%ld ts_offset=%ld first_pts=%ld\n",
+                            pkt->stream_index, pkt->pts, pkt->dts,
+                            c->play_state.ts_offset, c->first_pts);
+    if (pkt->pts < 0)
+        av_log(s, AV_LOG_WARNING, "Invalid frame PTS @ st=%d pts=%ld dts=%ld\n",
+                                  pkt->stream_index, pkt->pts, pkt->dts);
+
+    return c->play_end ? AVERROR_EOF : 0;
+}
+
+static int dvdvideo_close(AVFormatContext *s)
+{
+    DVDVideoDemuxContext *c = s->priv_data;
+
+    dvdvideo_subdemux_close(s);
+    dvdvideo_play_close(s, &c->play_state);
+    dvdvideo_ifo_close(s);
+
+    return 0;
+}
+
+#define OFFSET(x) offsetof(DVDVideoDemuxContext, x)
+static const AVOption dvdvideo_options[] = {
+    {"angle",           "playback angle number",                                    OFFSET(opt_angle),          AV_OPT_TYPE_INT,    { .i64=1 },     1,          9,         AV_OPT_FLAG_DECODING_PARAM },
+    {"chapter_end",     "exit chapter (PTT) number (0=end)",                        OFFSET(opt_chapter_end),    AV_OPT_TYPE_INT,    { .i64=0 },     0,          99,        AV_OPT_FLAG_DECODING_PARAM },
+    {"chapter_start",   "entry chapter (PTT) number",                               OFFSET(opt_chapter_start),  AV_OPT_TYPE_INT,    { .i64=1 },     1,          99,        AV_OPT_FLAG_DECODING_PARAM },
+    {"pg",              "entry PG number (0=auto)",                                 OFFSET(opt_pg),             AV_OPT_TYPE_INT,    { .i64=0 },     0,          255,       AV_OPT_FLAG_DECODING_PARAM },
+    {"pgc",             "entry PGC number (0=auto)",                                OFFSET(opt_pgc),            AV_OPT_TYPE_INT,    { .i64=0 },     0,          999,       AV_OPT_FLAG_DECODING_PARAM },
+    {"preindex",        "enable for accurate chapter markers, slow (2-pass read)",  OFFSET(opt_preindex),       AV_OPT_TYPE_BOOL,   { .i64=0 },     0,          1,         AV_OPT_FLAG_DECODING_PARAM },
+    {"region",          "playback region number (0=free)",                          OFFSET(opt_region),         AV_OPT_TYPE_INT,    { .i64=0 },     0,          8,         AV_OPT_FLAG_DECODING_PARAM },
+    {"title",           "title number (0=auto)",                                    OFFSET(opt_title),          AV_OPT_TYPE_INT,    { .i64=0 },     0,          99,        AV_OPT_FLAG_DECODING_PARAM },
+    {"trim",            "trim padding cells from start",                            OFFSET(opt_trim),           AV_OPT_TYPE_BOOL,   { .i64=1 },     0,          1,         AV_OPT_FLAG_DECODING_PARAM },
+    {NULL}
+};
+
+static const AVClass dvdvideo_class = {
+    .class_name = "DVD-Video demuxer",
+    .item_name  = av_default_item_name,
+    .option     = dvdvideo_options,
+    .version    = LIBAVUTIL_VERSION_INT
+};
+
+const AVInputFormat ff_dvdvideo_demuxer = {
+    .name           = "dvdvideo",
+    .long_name      = NULL_IF_CONFIG_SMALL("DVD-Video"),
+    .priv_class     = &dvdvideo_class,
+    .priv_data_size = sizeof(DVDVideoDemuxContext),
+    .flags          = AVFMT_NOFILE | AVFMT_SHOW_IDS | AVFMT_TS_DISCONT | AVFMT_NO_BYTE_SEEK | AVFMT_NOGENSEARCH | AVFMT_NOBINSEARCH,
+    .flags_internal = FF_FMT_INIT_CLEANUP,
+    .read_close     = dvdvideo_close,
+    .read_header    = dvdvideo_read_header,
+    .read_packet    = dvdvideo_read_packet
+};
-- 
2.34.1



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