[FFmpeg-devel] [PATCH] RealText demuxer and decoder.

Paul B Mahol onemda at gmail.com
Sun Jun 17 00:50:18 CEST 2012


On 6/16/12, Clement Boesch <ubitux at gmail.com> wrote:
> FIXME: bump minor in lavc & lavf
> ---
> To be applied on top of the previous patchset
> (github/ubitux/ffmpeg/subtitles
> is up-to-date, and includes this patch). The SMIL parser (in the demuxer) is
> more reliable than the one in SAMI (which I will update soon if I don't feel
> lazy).
> ---
>  doc/general.texi            |    1 +
>  libavcodec/Makefile         |    1 +
>  libavcodec/allcodecs.c      |    1 +
>  libavcodec/avcodec.h        |    1 +
>  libavcodec/realtextdec.c    |   81 ++++++++++++++++++++
>  libavformat/Makefile        |    1 +
>  libavformat/allformats.c    |    1 +
>  libavformat/realtextdec.c   |  172
> +++++++++++++++++++++++++++++++++++++++++++
>  tests/fate/subtitles.mak    |    3 +
>  tests/ref/fate/sub-realtext |    1 +
>  10 files changed, 263 insertions(+)
>  create mode 100644 libavcodec/realtextdec.c
>  create mode 100644 libavformat/realtextdec.c
>  create mode 100644 tests/ref/fate/sub-realtext
>
> diff --git a/doc/general.texi b/doc/general.texi
> index def03e3..72d09ae 100644
> --- a/doc/general.texi
> +++ b/doc/general.texi
> @@ -842,6 +842,7 @@ performance on systems without hardware floating point
> support).
>  @item JACOsub      @tab X @tab X @tab   @tab X
>  @item MicroDVD     @tab X @tab X @tab   @tab X
>  @item PGS          @tab   @tab   @tab   @tab X
> + at item RealText     @tab   @tab X @tab   @tab X
>  @item SAMI         @tab   @tab X @tab   @tab X
>  @item SubRip (SRT) @tab X @tab X @tab X @tab X
>  @item XSUB         @tab   @tab   @tab X @tab X
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index 668b4cd..ca58320 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -384,6 +384,7 @@ OBJS-$(CONFIG_ROQ_ENCODER)             += roqvideoenc.o
> roqvideo.o elbg.o
>  OBJS-$(CONFIG_ROQ_DPCM_DECODER)        += dpcm.o
>  OBJS-$(CONFIG_ROQ_DPCM_ENCODER)        += roqaudioenc.o
>  OBJS-$(CONFIG_RPZA_DECODER)            += rpza.o
> +OBJS-$(CONFIG_REALTEXT_DECODER)        += realtextdec.o ass.o
>  OBJS-$(CONFIG_RV10_DECODER)            += rv10.o
>  OBJS-$(CONFIG_RV10_ENCODER)            += rv10enc.o
>  OBJS-$(CONFIG_RV20_DECODER)            += rv10.o
> diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
> index 1eda64f..cf9e32e 100644
> --- a/libavcodec/allcodecs.c
> +++ b/libavcodec/allcodecs.c
> @@ -402,6 +402,7 @@ void avcodec_register_all(void)
>      REGISTER_DECODER (JACOSUB, jacosub);
>      REGISTER_DECODER (MICRODVD, microdvd);
>      REGISTER_DECODER (PGSSUB, pgssub);
> +    REGISTER_DECODER (REALTEXT, realtext);
>      REGISTER_DECODER (SAMI, sami);
>      REGISTER_ENCDEC  (SRT, srt);
>      REGISTER_ENCDEC  (XSUB, xsub);
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 952d846..7e874ad 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -427,6 +427,7 @@ enum CodecID {
>      CODEC_ID_EIA_608    = MKBETAG('c','6','0','8'),
>      CODEC_ID_JACOSUB    = MKBETAG('J','S','U','B'),
>      CODEC_ID_SAMI       = MKBETAG('S','A','M','I'),
> +    CODEC_ID_REALTEXT   = MKBETAG('R','T','X','T'),
>
>      /* other specific kind of codecs (generally used for attachments) */
>      CODEC_ID_FIRST_UNKNOWN = 0x18000,           ///< A dummy ID pointing at
> the start of various fake codecs.
> diff --git a/libavcodec/realtextdec.c b/libavcodec/realtextdec.c
> new file mode 100644
> index 0000000..512bfc1
> --- /dev/null
> +++ b/libavcodec/realtextdec.c
> @@ -0,0 +1,81 @@
> +/*
> + * Copyright (c) 2012 Clement Boesch
> + *
> + * 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
> + */
> +
> +/**
> + * @file
> + * RealText subtitle decoder
> + * @see
> http://service.real.com/help/library/guides/ProductionGuide/prodguide/htmfiles/realtext.htm
> + */
> +
> +#include "avcodec.h"
> +#include "ass.h"
> +#include "libavutil/avstring.h"
> +#include "libavutil/bprint.h"
> +
> +static int rt_event_to_ass(AVBPrint *buf, const char *p)
> +{
> +    int prev_chr_is_space = 1;
> +
> +    while (*p) {
> +        if (*p != '<') {
> +            if (!isspace(*p))
> +                av_bprint_chars(buf, *p, 1);
> +            else if (!prev_chr_is_space)
> +                av_bprint_chars(buf, ' ', 1);
> +            prev_chr_is_space = isspace(*p);
> +        } else {
> +            const char *end = strchr(p, '>');
> +            if (!end)
> +                break;
> +            if (!av_strncasecmp(p, "<br/>", 5) ||
> +                !av_strncasecmp(p, "<br>",  4)) {
> +                av_bprintf(buf, "\\N");
> +            }
> +            p = end;
> +        }
> +        p++;
> +    }
> +    av_bprintf(buf, "\r\n");
> +    return 0;
> +}
> +
> +static int realtext_decode_frame(AVCodecContext *avctx,
> +                                 void *data, int *got_sub_ptr, AVPacket
> *avpkt)
> +{
> +    AVSubtitle *sub = data;
> +    const char *ptr = avpkt->data;
> +    AVBPrint buf;
> +
> +    av_bprint_init(&buf, 0, 4096);
> +    if (ptr && avpkt->size > 0 && !rt_event_to_ass(&buf, ptr))
> +        ff_ass_add_rect(sub, buf.str, avpkt->pts, avpkt->duration, 0);
> +    *got_sub_ptr = sub->num_rects > 0;
> +    av_bprint_finalize(&buf, NULL);
> +    return avpkt->size;
> +}
> +
> +AVCodec ff_realtext_decoder = {
> +    .name           = "realtext",
> +    .long_name      = NULL_IF_CONFIG_SMALL("RealText subtitle"),
> +    .type           = AVMEDIA_TYPE_SUBTITLE,
> +    .id             = CODEC_ID_REALTEXT,
> +    .decode         = realtext_decode_frame,
> +    .init           = ff_ass_subtitle_header_default,
> +};
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 0771271..5f330dc 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -261,6 +261,7 @@ OBJS-$(CONFIG_ROQ_MUXER)                 += idroqenc.o
> rawenc.o
>  OBJS-$(CONFIG_RSO_DEMUXER)               += rsodec.o rso.o pcm.o
>  OBJS-$(CONFIG_RSO_MUXER)                 += rsoenc.o rso.o
>  OBJS-$(CONFIG_RPL_DEMUXER)               += rpl.o
> +OBJS-$(CONFIG_REALTEXT_DEMUXER)          += realtextdec.o

nit: Aren't entries sorted?
>  OBJS-$(CONFIG_RTP_MUXER)                 += rtp.o         \
>                                              rtpenc_aac.o     \
>                                              rtpenc_latm.o    \
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index b383218..1cff964 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -203,6 +203,7 @@ void av_register_all(void)
>      REGISTER_MUXDEMUX (ROQ, roq);
>      REGISTER_DEMUXER  (RPL, rpl);
>      REGISTER_MUXDEMUX (RSO, rso);
> +    REGISTER_DEMUXER  (REALTEXT, realtext);

ditto.
>      REGISTER_MUXDEMUX (RTP, rtp);
>      REGISTER_MUXDEMUX (RTSP, rtsp);
>      REGISTER_DEMUXER  (SAMI, sami);
> +        if (n == 0)
> +            break;
> +
> +        if (!av_strncasecmp(buf.str, "<window", 7)) {
> +            /* save header to extradata */
> +            char *p = get_attr_ptr(buf.str, "duration");
> +
> +            if (p)
> +                duration = read_ts(p);
> +            st->codec->extradata = av_strdup(buf.str);

This may fail.
> +            st->codec->extradata_size = buf.len + 1;
> +        } else {
> +            /* if we just read a <time> tag, introduce a new event,
> otherwise merge
> +             * with the previous one */
> +            merge = !av_strncasecmp(buf.str, "<time", 5) ? 0 : 1;
> +            sub = ff_subtitles_queue_insert_event(&rt->q, buf.str, buf.len,
> merge);
> +            if (!sub)
> +                return AVERROR(ENOMEM);
> +            if (!merge) {
> +                const char *begin = get_attr_ptr(buf.str, "begin");
> +                const char *end   = get_attr_ptr(buf.str, "end");
> +
> +                sub->pos      = pos;
> +                sub->start    = begin ? read_ts(begin) : 0;
> +                sub->duration = end ? (read_ts(end) - sub->start) :
> duration;
> +            }
> +        }
> +        av_bprint_clear(&buf);
> +    }
> +    ff_subtitles_queue_finalize(&rt->q);
> +    av_bprint_finalize(&buf, NULL);
> +    return 0;
> +}
> +
> +static int realtext_read_packet(AVFormatContext *s, AVPacket *pkt)
> +{
> +    RealTextContext *rt = s->priv_data;
> +    return ff_subtitles_queue_read_packet(&rt->q, pkt, rt->sid++);
> +}
> +
> +static int realtext_read_close(AVFormatContext *s)
> +{
> +    RealTextContext *rt = s->priv_data;
> +    ff_subtitles_queue_free(&rt->q);
> +    return 0;
> +}
> +
> +AVInputFormat ff_realtext_demuxer = {
> +    .name           = "realtext",
> +    .long_name      = NULL_IF_CONFIG_SMALL("RealText subtitle format"),
> +    .priv_data_size = sizeof(RealTextContext),
> +    .read_probe     = realtext_probe,
> +    .read_header    = realtext_read_header,
> +    .read_packet    = realtext_read_packet,
> +    .read_close     = realtext_read_close,
> +    .flags          = AVFMT_GENERIC_INDEX,
> +    .extensions     = "rt",
> +};
> diff --git a/tests/fate/subtitles.mak b/tests/fate/subtitles.mak
> index 78b9503..e56a056 100644
> --- a/tests/fate/subtitles.mak
> +++ b/tests/fate/subtitles.mak
> @@ -10,6 +10,9 @@ fate-sub-sami: CMD = md5 -i
> $(SAMPLES)/sub/SAMI_capability_tester.smi -f ass
>  FATE_SUBTITLES += fate-sub-srt
>  fate-sub-srt: CMD = md5 -i $(SAMPLES)/sub/SubRip_capability_tester.srt -f
> ass
>
> +FATE_SUBTITLES += fate-sub-realtext
> +fate-sub-realtext: CMD = md5 -i
> $(SAMPLES)/sub/RealText_capability_tester.rt -f ass
> +
>  FATE_SUBTITLES += $(FATE_SUBTITLES-yes)
>
>  FATE_SAMPLES_FFMPEG += $(FATE_SUBTITLES)
> diff --git a/tests/ref/fate/sub-realtext b/tests/ref/fate/sub-realtext
> new file mode 100644
> index 0000000..42ac3bb
> --- /dev/null
> +++ b/tests/ref/fate/sub-realtext
> @@ -0,0 +1 @@
> +5366f62be001f6fd4a7f48893828bf51
> --
> 1.7.10.4
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>


More information about the ffmpeg-devel mailing list