[FFmpeg-devel] [PATCH 3/4] Silicon Graphics Movie (.mv) demuxer

Paul B Mahol onemda at gmail.com
Tue Dec 11 12:32:06 CET 2012


On 12/11/12, Peter Ross <pross at xvid.org> wrote:
> Signed-off-by: Peter Ross <pross at xvid.org>
> ---
>  Changelog                |   1 +
>  doc/general.texi         |   1 +
>  libavformat/Makefile     |   1 +
>  libavformat/allformats.c |   1 +
>  libavformat/mvdec.c      | 410
> +++++++++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 414 insertions(+)
>  create mode 100644 libavformat/mvdec.c
>
> diff --git a/Changelog b/Changelog
> index 93f34e3..f2fd229 100644
> --- a/Changelog
> +++ b/Changelog
> @@ -42,6 +42,7 @@ version <next>:
>  - JSON captions for TED talks decoding support
>  - SGI RLE 8-bit decoder
>  - Silicon Graphics Motion Video Compressor 1 & 2 decoder
> +- Silicon Graphics Movie demuxer
>
>
>  version 1.0:
> diff --git a/doc/general.texi b/doc/general.texi
> index 22988b2..921bdcd 100644
> --- a/doc/general.texi
> +++ b/doc/general.texi
> @@ -359,6 +359,7 @@ library:
>  @item SDP                       @tab   @tab X
>  @item Sega FILM/CPK             @tab   @tab X
>      @tab Used in many Sega Saturn console games.
> + at item Silicon Graphics Movie    @tab   @tab X
>  @item Sierra SOL                @tab   @tab X
>      @tab .sol files used in Sierra Online games.
>  @item Sierra VMD                @tab   @tab X
> diff --git a/libavformat/Makefile b/libavformat/Makefile
> index 87fdc11..b187697 100644
> --- a/libavformat/Makefile
> +++ b/libavformat/Makefile
> @@ -222,6 +222,7 @@ OBJS-$(CONFIG_MPJPEG_MUXER)              += mpjpeg.o
>  OBJS-$(CONFIG_MSNWC_TCP_DEMUXER)         += msnwc_tcp.o
>  OBJS-$(CONFIG_MTV_DEMUXER)               += mtv.o
>  OBJS-$(CONFIG_MVI_DEMUXER)               += mvi.o
> +OBJS-$(CONFIG_MV_DEMUXER)                += mvdec.o
>  OBJS-$(CONFIG_MXF_DEMUXER)               += mxfdec.o mxf.o
>  OBJS-$(CONFIG_MXF_MUXER)                 += mxfenc.o mxf.o
> audiointerleave.o
>  OBJS-$(CONFIG_MXG_DEMUXER)               += mxg.o
> diff --git a/libavformat/allformats.c b/libavformat/allformats.c
> index 8e8a799..6456e8c 100644
> --- a/libavformat/allformats.c
> +++ b/libavformat/allformats.c
> @@ -172,6 +172,7 @@ void av_register_all(void)
>      REGISTER_MUXER    (MPJPEG, mpjpeg);
>      REGISTER_DEMUXER  (MSNWC_TCP, msnwc_tcp);
>      REGISTER_DEMUXER  (MTV, mtv);
> +    REGISTER_DEMUXER  (MV, mv);
>      REGISTER_DEMUXER  (MVI, mvi);
>      REGISTER_MUXDEMUX (MXF, mxf);
>      REGISTER_MUXER    (MXF_D10, mxf_d10);
> diff --git a/libavformat/mvdec.c b/libavformat/mvdec.c
> new file mode 100644
> index 0000000..3f7816d
> --- /dev/null
> +++ b/libavformat/mvdec.c
> @@ -0,0 +1,410 @@
> +/*
> + * Silicon Graphics Movie demuxer
> + * Copyright (c) 2012 Peter Ross
> + *
> + * 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
> + * Silicon Graphics Movie demuxer
> + */
> +
> +#include "libavutil/intreadwrite.h"
> +#include "libavutil/rational.h"
> +#include "avformat.h"
> +#include "internal.h"
> +
> +typedef struct {
> +    int nb_video_tracks;
> +    int nb_audio_tracks;
> +
> +    int eof_count;        /**< number of streams that have finished */
> +    int stream_index;     /**< current stream index */
> +    int frame[2];         /**< frame nb for current stream */
> +} MvContext;
> +
> +static int mv_probe(AVProbeData *p)
> +{
> +    if (AV_RB32(p->buf) == MKBETAG('M','O','V','I') && AV_RB16(p->buf + 4)
> < 3)
> +        return AVPROBE_SCORE_MAX;
> +    return 0;
> +}
> +
> +static int var_read_int(AVIOContext *pb, int size)
> +{
> +    int value = 0;
> +    while (size--) {
> +        int c = avio_r8(pb);
> +        if (c < '0' || c > '9')
> +            break;
> +        value = value * 10 + c - '0';
> +    }
> +    avio_skip(pb, size);
> +    return value;
> +}

isn't there already something like lavu/parseutils and eval?
> +
> +static AVRational var_read_float(AVIOContext *pb, int size)
> +{
> +    AVRational v = { 0, 1 };
> +    int fractional = 0;
> +    while (size--) {
> +        int c = avio_r8(pb);
> +        if (c == '.') {
> +            if (fractional)
> +                break;
> +            fractional = 1;
> +            continue;
> +        }
> +        if (c < '0' || c > '9')
> +            break;
> +        v.num = v.num * 10 + c - '0';
> +        if (fractional)
> +            v.den *= 10;
> +    }
> +    avio_skip(pb, size);
> +    return v;
> +}

ditto
> +
> +static char * var_read_string(AVIOContext *pb, int size)
> +{
> +    char *str = av_malloc(size + 1);
> +    if (!str)
> +        return NULL;
> +    avio_read(pb, str, size);
> +    str[size] = 0;
> +    return str;
> +}

avio_get_str() + avio_skip() (if strings have extra padding)
> +
> +static void var_read_metadata(AVFormatContext *avctx, const char *tag, int
> size)
> +{
> +    char *value = var_read_string(avctx->pb, size);
> +    if (value)
> +        av_dict_set(&avctx->metadata, tag, value,
> AV_DICT_DONT_STRDUP_VAL);
> +}
> +
> +/**
> + * Parse global variable
> + * @return < 0 if unknown
> + */
> +static int parse_global_var(AVFormatContext *avctx, AVStream *st, const
> char *name, int size)
> +{
> +    MvContext *mv = avctx->priv_data;
> +    AVIOContext *pb = avctx->pb;
> +    if (!strcmp(name, "__NUM_I_TRACKS")) {
> +        mv->nb_video_tracks = var_read_int(pb, size);
> +    } else if (!strcmp(name, "__NUM_A_TRACKS")) {
> +        mv->nb_audio_tracks = var_read_int(pb, size);
> +    } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
> +        var_read_metadata(avctx, name, size);
> +    } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") ||
> !strcmp(name, "OPTIMIZED")) {
> +        avio_skip(pb, size); // ignore
> +    } else
> +        return -1;
> +
> +    return 0;
> +}
> +
> +/**
> + * Parse audio variable
> + * @return < 0 if unknown
> + */
> +static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char
> *name, int size)
> +{
> +    AVIOContext *pb = avctx->pb;
> +    if (!strcmp(name, "__DIR_COUNT")) {
> +        st->nb_frames = var_read_int(pb, size);
> +    } else if (!strcmp(name, "AUDIO_FORMAT")) {
> +        st->codec->codec_id = var_read_int(pb, size);
> +    } else if (!strcmp(name, "COMPRESSION")) {
> +        st->codec->codec_tag = var_read_int(pb, size);
> +    } else if (!strcmp(name, "DEFAULT_VOL")) {
> +        var_read_metadata(avctx, name, size);
> +    } else if (!strcmp(name, "NUM_CHANNELS")) {
> +        st->codec->channels = var_read_int(pb, size);
> +        st->codec->channel_layout = (st->codec->channels == 1) ?
> AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
> +    } else if (!strcmp(name, "SAMPLE_RATE")) {
> +        st->codec->sample_rate = var_read_int(pb, size);
> +        avpriv_set_pts_info(st, 33, 1, st->codec->sample_rate);
> +    } else if (!strcmp(name, "SAMPLE_WIDTH")) {
> +        st->codec->bits_per_coded_sample = var_read_int(pb, size) * 8;
> +    } else
> +        return -1;
> +    return 0;
> +}
> +
> +/**
> + * Parse video variable
> + * @return < 0 if unknown
> + */
> +static int parse_video_var(AVFormatContext *avctx, AVStream *st, const char
> *name, int size)
> +{
> +    AVIOContext *pb = avctx->pb;
> +    if (!strcmp(name, "__DIR_COUNT")) {
> +        st->nb_frames = st->duration = var_read_int(pb, size);
> +    } else if (!strcmp(name, "COMPRESSION")) {
> +        char * str = var_read_string(pb, size);
> +        if (!strcmp(str, "1")) {
> +            st->codec->codec_id = AV_CODEC_ID_MVC1;
> +        } else if (!strcmp(str, "2")) {
> +            st->codec->pix_fmt  = AV_PIX_FMT_ABGR;
> +            st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
> +        } else if (!strcmp(str, "3")) {
> +            st->codec->codec_id = AV_CODEC_ID_SGIRLE;
> +        } else if (!strcmp(str, "10")) {
> +            st->codec->codec_id = AV_CODEC_ID_MJPEG;
> +        } else if (!strcmp(str, "MVC2")) {
> +            st->codec->codec_id = AV_CODEC_ID_MVC2;
> +        } else {
> +            av_log_ask_for_sample(avctx, "unknown video compression\n");
> +        }
> +        av_free(str);
> +    } else if (!strcmp(name, "FPS")) {
> +        st->time_base = av_inv_q(var_read_float(pb, size));
> +    } else if (!strcmp(name, "HEIGHT")) {
> +        st->codec->height = var_read_int(pb, size);
> +    } else if (!strcmp(name, "PIXEL_ASPECT")) {
> +        st->sample_aspect_ratio = var_read_float(pb, size);
> +        av_reduce(&st->sample_aspect_ratio.num,
> &st->sample_aspect_ratio.den,
> +                  st->sample_aspect_ratio.num, st->sample_aspect_ratio.den,
> INT_MAX);
> +    } else if (!strcmp(name, "WIDTH")) {
> +        st->codec->width = var_read_int(pb, size);
> +    } else if (!strcmp(name, "ORIENTATION")) {
> +        if (var_read_int(pb, size) == 1101) {
> +            st->codec->extradata       = av_strdup("BottomUp");
> +            st->codec->extradata_size  = 9;
> +        }
> +    } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL"))
> {
> +        var_read_metadata(avctx, name, size);
> +    } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
> +        avio_skip(pb, size); // ignore
> +    } else
> +        return -1;
> +    return 0;
> +}
> +
> +static void read_table(AVFormatContext *avctx, AVStream *st, int
> (*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
> +{
> +    int count, i;
> +    AVIOContext *pb = avctx->pb;
> +    avio_skip(pb, 4);
> +    count = avio_rb32(pb);
> +    avio_skip(pb, 4);
> +    for (i = 0; i < count; i++) {
> +        char name[17];
> +        int size;
> +        avio_read(pb, name, 16);
> +        name[sizeof(name) - 1] = 0;
> +        size = avio_rb32(pb);
> +        if (parse(avctx, st, name, size) < 0) {
> +            av_log_ask_for_sample(avctx, "unknown variable %s\n", name);
> +            avio_skip(pb, size);
> +        }
> +    }
> +}
> +
> +static void read_index(AVIOContext *pb, AVStream *st)
> +{
> +    uint64_t timestamp = 0;
> +    int i;
> +    for (i = 0; i < st->nb_frames; i++) {
> +        uint32_t pos  = avio_rb32(pb);
> +        uint32_t size = avio_rb32(pb);
> +        avio_skip(pb, 8);
> +        av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
> +        if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
> +            timestamp += size / (st->codec->channels * 2);
> +        } else {
> +            timestamp++;
> +        }
> +    }
> +}
> +
> +static int mv_read_header(AVFormatContext *avctx)
> +{
> +    MvContext *mv = avctx->priv_data;
> +    AVIOContext *pb = avctx->pb;
> +    AVStream *ast, *vst;
> +    int version, i;
> +
> +    avio_skip(pb, 4);
> +
> +    version = avio_rb16(pb);
> +    if (version == 2) {
> +        uint64_t timestamp;
> +        avio_skip(pb, 22);
> +        vst = avformat_new_stream(avctx, NULL);
> +        if (!vst)
> +            return AVERROR(ENOMEM);
> +        vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
> +        vst->time_base = (AVRational){1, 15};
> +
> +        vst->nb_frames = avio_rb32(pb);
> +        vst->codec->codec_tag = avio_rb32(pb);

not really codec->codec_tag to be exported this way.
> +        switch (vst->codec->codec_tag) {
> +        case 1:
> +            vst->codec->codec_id = AV_CODEC_ID_MVC1;
> +            break;
> +        case 2:
> +            vst->codec->pix_fmt  = AV_PIX_FMT_ARGB;
> +            vst->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
> +            break;
> +        default:
> +            av_log_ask_for_sample(avctx, "unknown video compression\n");
> +            break;
> +        }
> +        vst->codec->width  = avio_rb32(pb);
> +        vst->codec->height = avio_rb32(pb);
> +        avio_skip(pb, 12);
> +
> +        ast = avformat_new_stream(avctx, NULL);
> +        if (!ast)
> +            return AVERROR(ENOMEM);
> +        ast->codec->codec_type     = AVMEDIA_TYPE_AUDIO;
> +        ast->nb_frames             = vst->nb_frames;
> +        ast->codec->sample_rate    = avio_rb32(pb);
> +        avpriv_set_pts_info(ast, 33, 1, ast->codec->sample_rate);
> +        ast->codec->channels       = avio_rb32(pb);
> +        ast->codec->channel_layout = (ast->codec->channels == 1) ?
> AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
> +        if (avio_rb32(pb) == 401) {
> +            ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
> +        } else {
> +            av_log_ask_for_sample(avctx, "unknown audio compression\n");
> +        }
> +
> +        avio_skip(pb, 12);

what is that? padding or something that tells where other data is located?
> +        var_read_metadata(avctx, "title", 0x80);
> +        var_read_metadata(avctx, "comment", 0x100);
> +        avio_skip(pb, 0x80);

ditto
> +
> +        timestamp = 0;
> +        for (i = 0; i < vst->nb_frames; i++) {
> +            uint32_t pos   = avio_rb32(pb);
> +            uint32_t asize = avio_rb32(pb);
> +            uint32_t vsize = avio_rb32(pb);
> +            avio_skip(pb, 8);

padding or?
> +            av_add_index_entry(ast, pos,         timestamp, asize, 0,
> AVINDEX_KEYFRAME);
> +            av_add_index_entry(vst, pos + asize, i,         vsize, 0,
> AVINDEX_KEYFRAME);
> +            timestamp += asize / (ast->codec->channels * 2);
> +        }
> +    } else if (!version && avio_rb16(pb) == 3) {
> +        avio_skip(pb, 4);
padding or?
> +
> +        read_table(avctx, NULL, parse_global_var);
> +
> +        if (mv->nb_audio_tracks > 1) {
> +            av_log_ask_for_sample(avctx, "multiple audio streams\n");
> +            return AVERROR_PATCHWELCOME;
> +        } else if (mv->nb_audio_tracks) {
> +            ast = avformat_new_stream(avctx, NULL);
> +            if (!ast)
> +                return AVERROR(ENOMEM);
> +            ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
> +            read_table(avctx, ast, parse_audio_var);
> +            if (ast->codec->codec_tag == 100 && ast->codec->codec_id == 401
> && ast->codec->bits_per_coded_sample == 16) {
> +                ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
> +            } else {
> +                av_log_ask_for_sample(avctx, "unknown audio
> compression\n");
> +            }
> +        }
> +
> +        if (mv->nb_video_tracks > 1) {
> +            av_log_ask_for_sample(avctx, "multiple video streams\n");
> +            return AVERROR_PATCHWELCOME;
> +        } else if (mv->nb_video_tracks) {
> +            vst = avformat_new_stream(avctx, NULL);
> +            if (!vst)
> +                return AVERROR(ENOMEM);
> +            vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
> +            read_table(avctx, vst, parse_video_var);
> +        }
> +
> +        if (mv->nb_audio_tracks)
> +            read_index(pb, ast);
> +
> +        if (mv->nb_video_tracks)
> +            read_index(pb, vst);
> +    } else {
> +        av_log_ask_for_sample(avctx, "unknown version\n");

Could you please for all unknown cases actually print unknown value.
> +        return AVERROR_PATCHWELCOME;
> +    }
> +
> +    return 0;
> +}
> +
> +static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
> +{
> +    MvContext *mv = avctx->priv_data;
> +    AVIOContext *pb = avctx->pb;
> +    AVStream *st = avctx->streams[mv->stream_index];
> +    const AVIndexEntry *index;
> +    int ret;
> +    int frame = mv->frame[mv->stream_index];
> +
> +    if (frame  < st->nb_frames) {
> +        index = &st->index_entries[frame];
> +        avio_seek(pb, index->pos, SEEK_SET);

??? is this really required? Demuxing via pipe protocol (or any that
do not support seeking)
still works?
> +        ret = av_get_packet(pb, pkt, index->size);
> +        if (ret < 0)
> +            return ret;
> +
> +        pkt->stream_index = mv->stream_index;
> +        pkt->pts = index->timestamp;
> +        pkt->flags |= AV_PKT_FLAG_KEY;
> +
> +        mv->frame[mv->stream_index]++;
> +        mv->eof_count = 0;
> +    } else {
> +        mv->eof_count++;
> +        if (mv->eof_count >= avctx->nb_streams)
> +            return AVERROR_EOF;
> +    }
> +
> +    mv->stream_index++;
> +    if (mv->stream_index >= avctx->nb_streams)
> +        mv->stream_index = 0;
> +
> +    return 0;
> +}
> +
> +static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t
> timestamp, int flags)
> +{
> +    MvContext *mv = avctx->priv_data;
> +    AVStream *st = avctx->streams[stream_index];
> +    int frame, i;
> +
> +    if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
> +        return AVERROR(ENOSYS);
> +
> +    frame = av_index_search_timestamp(st, timestamp, flags);
> +    if (frame < 0)
> +        return -1;
> +
> +    for (i = 0; i < avctx->nb_streams; i++)
> +        mv->frame[i] = frame;
> +    return 0;
> +}
> +
> +AVInputFormat ff_mv_demuxer = {
> +    .name           = "mv",
> +    .long_name      = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
> +    .priv_data_size = sizeof(MvContext),
> +    .read_probe     = mv_probe,
> +    .read_header    = mv_read_header,
> +    .read_packet    = mv_read_packet,
> +    .read_seek      = mv_read_seek,
> +};
> --
> 1.8.0
>
> -- Peter
> (A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
>


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