[FFmpeg-devel] [PATCH 2/8] timecode: introduce timecode and honor it in MPEG-1/2.
Clément Bœsch
ubitux at gmail.com
Wed Jul 27 18:45:12 CEST 2011
From: Clément Bœsch <clement.boesch at smartjog.com>
This is based on the original work by Baptiste Coudurier.
---
libavcodec/Makefile | 2 +
libavcodec/mpeg12enc.c | 26 +++++++++++++++++++-
libavcodec/mpegvideo.h | 4 +++
libavcodec/timecode.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++
libavcodec/timecode.h | 58 ++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 144 insertions(+), 2 deletions(-)
create mode 100644 libavcodec/timecode.c
create mode 100644 libavcodec/timecode.h
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 9706939..363879c 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -260,6 +260,7 @@ OBJS-$(CONFIG_MPEG_XVMC_DECODER) += mpegvideo_xvmc.o
OBJS-$(CONFIG_MPEG1VIDEO_DECODER) += mpeg12.o mpeg12data.o \
mpegvideo.o error_resilience.o
OBJS-$(CONFIG_MPEG1VIDEO_ENCODER) += mpeg12enc.o mpegvideo_enc.o \
+ timecode.o \
motion_est.o ratecontrol.o \
mpeg12.o mpeg12data.o \
mpegvideo.o error_resilience.o
@@ -268,6 +269,7 @@ OBJS-$(CONFIG_MPEG2_VAAPI_HWACCEL) += vaapi_mpeg2.o
OBJS-$(CONFIG_MPEG2VIDEO_DECODER) += mpeg12.o mpeg12data.o \
mpegvideo.o error_resilience.o
OBJS-$(CONFIG_MPEG2VIDEO_ENCODER) += mpeg12enc.o mpegvideo_enc.o \
+ timecode.o \
motion_est.o ratecontrol.o \
mpeg12.o mpeg12data.o \
mpegvideo.o error_resilience.o
diff --git a/libavcodec/mpeg12enc.c b/libavcodec/mpeg12enc.c
index 1729fb1..021f35e 100644
--- a/libavcodec/mpeg12enc.c
+++ b/libavcodec/mpeg12enc.c
@@ -32,6 +32,8 @@
#include "mpeg12.h"
#include "mpeg12data.h"
#include "bytestream.h"
+#include "timecode.h"
+#include "libavutil/opt.h"
static const uint8_t inv_non_linear_qscale[13] = {
@@ -172,11 +174,18 @@ static av_cold int encode_init(AVCodecContext *avctx)
}
}
+ s->tc.drop = !!(avctx->flags2 & CODEC_FLAG2_DROP_FRAME_TIMECODE);
if((avctx->flags2 & CODEC_FLAG2_DROP_FRAME_TIMECODE) && s->frame_rate_index != 4){
av_log(avctx, AV_LOG_ERROR, "Drop frame time code only allowed with 1001/30000 fps\n");
return -1;
}
+ if (s->tc.str) {
+ s->tc.rate = ff_frame_rate_tab[s->frame_rate_index];
+ if (ff_init_smtpe_timecode(s, &s->tc) < 0)
+ return -1;
+ s->avctx->timecode_frame_start = s->tc.start;
+ }
return 0;
}
@@ -283,14 +292,14 @@ static void mpeg1_encode_sequence_header(MpegEncContext *s)
}
put_header(s, GOP_START_CODE);
- put_bits(&s->pb, 1, !!(s->avctx->flags2 & CODEC_FLAG2_DROP_FRAME_TIMECODE)); /* drop frame flag */
+ put_bits(&s->pb, 1, s->tc.drop);
/* time code : we must convert from the real frame rate to a
fake mpeg frame rate in case of low frame rate */
fps = (framerate.num + framerate.den/2)/ framerate.den;
time_code = s->current_picture_ptr->f.coded_picture_number + s->avctx->timecode_frame_start;
s->gop_picture_number = s->current_picture_ptr->f.coded_picture_number;
- if (s->avctx->flags2 & CODEC_FLAG2_DROP_FRAME_TIMECODE) {
+ if (s->tc.drop) {
/* only works for NTSC 29.97 */
int d = time_code / 17982;
int m = time_code % 17982;
@@ -925,6 +934,17 @@ static void mpeg1_encode_block(MpegEncContext *s,
put_bits(&s->pb, table_vlc[112][1], table_vlc[112][0]);
}
+static const AVClass class = {
+ .class_name = "mpegvideo",
+ .item_name = av_default_item_name,
+ .version = LIBAVUTIL_VERSION_INT,
+ .option = (const AVOption[]){
+ {TIMECODE_OPT(MpegEncContext,
+ AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)},
+ {NULL}
+ },
+};
+
AVCodec ff_mpeg1video_encoder = {
"mpeg1video",
AVMEDIA_TYPE_VIDEO,
@@ -937,6 +957,7 @@ AVCodec ff_mpeg1video_encoder = {
.pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_NONE},
.capabilities= CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
.long_name= NULL_IF_CONFIG_SMALL("MPEG-1 video"),
+ .priv_class = &class,
};
AVCodec ff_mpeg2video_encoder = {
@@ -951,4 +972,5 @@ AVCodec ff_mpeg2video_encoder = {
.pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_YUV422P, PIX_FMT_NONE},
.capabilities= CODEC_CAP_DELAY | CODEC_CAP_SLICE_THREADS,
.long_name= NULL_IF_CONFIG_SMALL("MPEG-2 video"),
+ .priv_class = &class,
};
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index 327e735..d18b4b5 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -36,6 +36,7 @@
#include "parser.h"
#include "mpeg12data.h"
#include "rl.h"
+#include "timecode.h"
#define FRAME_SKIPPED 100 ///< return value for header parsers if frame is not coded
@@ -199,6 +200,7 @@ typedef struct MotionEstContext{
* MpegEncContext.
*/
typedef struct MpegEncContext {
+ AVClass *av_class;
struct AVCodecContext *avctx;
/* the following parameters must be initialized before encoding */
int width, height;///< picture size. must be a multiple of 16
@@ -647,6 +649,8 @@ typedef struct MpegEncContext {
/* RTP specific */
int rtp_mode;
+ struct ff_timecode tc;
+
uint8_t *ptr_lastgob;
int swap_uv; //vcr2 codec is an MPEG-2 variant with U and V swapped
DCTELEM (*pblocks[12])[64];
diff --git a/libavcodec/timecode.c b/libavcodec/timecode.c
new file mode 100644
index 0000000..d9c3f7d
--- /dev/null
+++ b/libavcodec/timecode.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier at gmail.com>
+ * Copyright (C) 2011 Smartjog S.A.S, Clément Bœsch <clement.boesch at smartjog.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation;
+ * version 2 of the License.
+ *
+ * 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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
+*/
+
+/**
+ * @file
+ * Timecode helpers
+ */
+
+#include <stdio.h>
+#include "timecode.h"
+#include "libavutil/log.h"
+
+int ff_init_smtpe_timecode(void *avcl, struct ff_timecode *tc)
+{
+ int hh, mm, ss, ff, fps;
+ char c;
+
+ if (sscanf(tc->str, "%d:%d:%d%c%d", &hh, &mm, &ss, &c, &ff) != 5) {
+ av_log(avcl, AV_LOG_ERROR, "unable to parse timecode, "
+ "syntax: hh:mm:ss[:;.]ff\n");
+ return -1;
+ }
+
+ fps = (tc->rate.num + tc->rate.den/2) / tc->rate.den;
+ tc->start = (hh*3600 + mm*60 + ss) * fps + ff;
+ tc->drop = c != ':'; // drop if ';', '.', ...
+
+ if (tc->drop) { /* adjust frame number */
+ int tmins = 60*hh + mm;
+ if (tc->rate.den != 1001 || fps != 30) {
+ av_log(avcl, AV_LOG_ERROR, "error: drop frame is only allowed with"
+ "30000/1001 FPS");
+ return -2;
+ }
+ tc->start -= 2 * (tmins - tmins/10);
+ }
+ return 0;
+}
diff --git a/libavcodec/timecode.h b/libavcodec/timecode.h
new file mode 100644
index 0000000..d2f6606
--- /dev/null
+++ b/libavcodec/timecode.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier at gmail.com>
+ * Copyright (C) 2011 Smartjog S.A.S, Clément Bœsch <clement.boesch at smartjog.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation;
+ * version 2 of the License.
+ *
+ * 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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
+ */
+
+/**
+ * @file
+ * Timecode helpers header
+ */
+
+#ifndef AVCODEC_TIMECODE_H
+#define AVCODEC_TIMECODE_H
+
+#include <stdint.h>
+#include "libavutil/rational.h"
+
+#define TIMECODE_OPT(ctx, flags) \
+ "timecode", "set timecode value following hh:mm:ss[:;.]ff format, " \
+ "use ';' or '.' before frame number for drop frame", \
+ offsetof(ctx, tc.str), \
+ FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, flags
+
+struct ff_timecode {
+ char *str; ///< string following the hh:mm:ss[:;.]ff format
+ int start; ///< timecode frame start
+ int drop; ///< drop flag (1 if drop, else 0)
+ AVRational rate; ///< Frame rate in rationnal form
+};
+
+/**
+ * Parse SMTPE 12M time representation (hh:mm:ss[:;.]ff). str and rate fields
+ * from tc struct must be set.
+ *
+ * @param avcl A pointer to an arbitrary struct of which the first field is a
+ * pointer to an AVClass struct (used for av_log).
+ * @param tc Timecode struct pointer
+ * @return 0 on success, negative value on failure
+ * @warning Adjustement is only valid in NTSC 29.97
+ */
+int ff_init_smtpe_timecode(void *avcl, struct ff_timecode *tc);
+
+#endif /* AVCODEC_TIMECODE_H */
--
1.7.5.4
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