yading@11: /*
yading@11:  * SMJPEG demuxer
yading@11:  * Copyright (c) 2011 Paul B Mahol
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * This is a demuxer for Loki SDL Motion JPEG files
yading@11:  */
yading@11: 
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: #include "riff.h"
yading@11: #include "smjpeg.h"
yading@11: 
yading@11: typedef struct SMJPEGContext {
yading@11:     int audio_stream_index;
yading@11:     int video_stream_index;
yading@11: } SMJPEGContext;
yading@11: 
yading@11: static int smjpeg_probe(AVProbeData *p)
yading@11: {
yading@11:     if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
yading@11:         return AVPROBE_SCORE_MAX;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int smjpeg_read_header(AVFormatContext *s)
yading@11: {
yading@11:     SMJPEGContext *sc = s->priv_data;
yading@11:     AVStream *ast = NULL, *vst = NULL;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     uint32_t version, htype, hlength, duration;
yading@11:     char *comment;
yading@11: 
yading@11:     avio_skip(pb, 8); // magic
yading@11:     version = avio_rb32(pb);
yading@11:     if (version)
yading@11:         avpriv_request_sample(s, "Unknown version %d", version);
yading@11: 
yading@11:     duration = avio_rb32(pb); // in msec
yading@11: 
yading@11:     while (!url_feof(pb)) {
yading@11:         htype = avio_rl32(pb);
yading@11:         switch (htype) {
yading@11:         case SMJPEG_TXT:
yading@11:             hlength = avio_rb32(pb);
yading@11:             if (!hlength || hlength > 512)
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             comment = av_malloc(hlength + 1);
yading@11:             if (!comment)
yading@11:                 return AVERROR(ENOMEM);
yading@11:             if (avio_read(pb, comment, hlength) != hlength) {
yading@11:                 av_freep(&comment);
yading@11:                 av_log(s, AV_LOG_ERROR, "error when reading comment\n");
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             }
yading@11:             comment[hlength] = 0;
yading@11:             av_dict_set(&s->metadata, "comment", comment,
yading@11:                         AV_DICT_DONT_STRDUP_VAL);
yading@11:             break;
yading@11:         case SMJPEG_SND:
yading@11:             if (ast) {
yading@11:                 avpriv_request_sample(s, "Multiple audio streams");
yading@11:                 return AVERROR_PATCHWELCOME;
yading@11:             }
yading@11:             hlength = avio_rb32(pb);
yading@11:             if (hlength < 8)
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             ast = avformat_new_stream(s, 0);
yading@11:             if (!ast)
yading@11:                 return AVERROR(ENOMEM);
yading@11:             ast->codec->codec_type  = AVMEDIA_TYPE_AUDIO;
yading@11:             ast->codec->sample_rate = avio_rb16(pb);
yading@11:             ast->codec->bits_per_coded_sample = avio_r8(pb);
yading@11:             ast->codec->channels    = avio_r8(pb);
yading@11:             ast->codec->codec_tag   = avio_rl32(pb);
yading@11:             ast->codec->codec_id    = ff_codec_get_id(ff_codec_smjpeg_audio_tags,
yading@11:                                                       ast->codec->codec_tag);
yading@11:             ast->duration           = duration;
yading@11:             sc->audio_stream_index  = ast->index;
yading@11:             avpriv_set_pts_info(ast, 32, 1, 1000);
yading@11:             avio_skip(pb, hlength - 8);
yading@11:             break;
yading@11:         case SMJPEG_VID:
yading@11:             if (vst) {
yading@11:                 avpriv_request_sample(s, "Multiple video streams");
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             }
yading@11:             hlength = avio_rb32(pb);
yading@11:             if (hlength < 12)
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             vst = avformat_new_stream(s, 0);
yading@11:             if (!vst)
yading@11:                 return AVERROR(ENOMEM);
yading@11:             vst->nb_frames         = avio_rb32(pb);
yading@11:             vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
yading@11:             vst->codec->width      = avio_rb16(pb);
yading@11:             vst->codec->height     = avio_rb16(pb);
yading@11:             vst->codec->codec_tag  = avio_rl32(pb);
yading@11:             vst->codec->codec_id   = ff_codec_get_id(ff_codec_smjpeg_video_tags,
yading@11:                                                      vst->codec->codec_tag);
yading@11:             vst->duration          = duration;
yading@11:             sc->video_stream_index = vst->index;
yading@11:             avpriv_set_pts_info(vst, 32, 1, 1000);
yading@11:             avio_skip(pb, hlength - 12);
yading@11:             break;
yading@11:         case SMJPEG_HEND:
yading@11:             return 0;
yading@11:         default:
yading@11:             av_log(s, AV_LOG_ERROR, "unknown header %x\n", htype);
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return AVERROR_EOF;
yading@11: }
yading@11: 
yading@11: static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     SMJPEGContext *sc = s->priv_data;
yading@11:     uint32_t dtype, size, timestamp;
yading@11:     int64_t pos;
yading@11:     int ret;
yading@11: 
yading@11:     if (url_feof(s->pb))
yading@11:         return AVERROR_EOF;
yading@11:     pos   = avio_tell(s->pb);
yading@11:     dtype = avio_rl32(s->pb);
yading@11:     switch (dtype) {
yading@11:     case SMJPEG_SNDD:
yading@11:         timestamp = avio_rb32(s->pb);
yading@11:         size = avio_rb32(s->pb);
yading@11:         ret = av_get_packet(s->pb, pkt, size);
yading@11:         pkt->stream_index = sc->audio_stream_index;
yading@11:         pkt->pts = timestamp;
yading@11:         pkt->pos = pos;
yading@11:         break;
yading@11:     case SMJPEG_VIDD:
yading@11:         timestamp = avio_rb32(s->pb);
yading@11:         size = avio_rb32(s->pb);
yading@11:         ret = av_get_packet(s->pb, pkt, size);
yading@11:         pkt->stream_index = sc->video_stream_index;
yading@11:         pkt->pts = timestamp;
yading@11:         pkt->pos = pos;
yading@11:         break;
yading@11:     case SMJPEG_DONE:
yading@11:         ret = AVERROR_EOF;
yading@11:         break;
yading@11:     default:
yading@11:         av_log(s, AV_LOG_ERROR, "unknown chunk %x\n", dtype);
yading@11:         ret = AVERROR_INVALIDDATA;
yading@11:         break;
yading@11:     }
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_smjpeg_demuxer = {
yading@11:     .name           = "smjpeg",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
yading@11:     .priv_data_size = sizeof(SMJPEGContext),
yading@11:     .read_probe     = smjpeg_probe,
yading@11:     .read_header    = smjpeg_read_header,
yading@11:     .read_packet    = smjpeg_read_packet,
yading@11:     .extensions     = "mjpg",
yading@11:     .flags          = AVFMT_GENERIC_INDEX,
yading@11: };