libavformat/thp.c
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00001 /*
00002  * THP Demuxer
00003  * Copyright (c) 2007 Marco Gerards
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/intreadwrite.h"
00023 #include "libavutil/intfloat.h"
00024 #include "avformat.h"
00025 #include "internal.h"
00026 
00027 typedef struct ThpDemuxContext {
00028     int              version;
00029     int              first_frame;
00030     int              first_framesz;
00031     int              last_frame;
00032     int              compoff;
00033     int              framecnt;
00034     AVRational       fps;
00035     int              frame;
00036     int              next_frame;
00037     int              next_framesz;
00038     int              video_stream_index;
00039     int              audio_stream_index;
00040     int              compcount;
00041     unsigned char    components[16];
00042     AVStream*        vst;
00043     int              has_audio;
00044     unsigned         audiosize;
00045 } ThpDemuxContext;
00046 
00047 
00048 static int thp_probe(AVProbeData *p)
00049 {
00050     /* check file header */
00051     if (AV_RL32(p->buf) == MKTAG('T', 'H', 'P', '\0'))
00052         return AVPROBE_SCORE_MAX;
00053     else
00054         return 0;
00055 }
00056 
00057 static int thp_read_header(AVFormatContext *s,
00058                            AVFormatParameters *ap)
00059 {
00060     ThpDemuxContext *thp = s->priv_data;
00061     AVStream *st;
00062     AVIOContext *pb = s->pb;
00063     int64_t fsize= avio_size(pb);
00064     int i;
00065 
00066     /* Read the file header.  */
00067                            avio_rb32(pb); /* Skip Magic.  */
00068     thp->version         = avio_rb32(pb);
00069 
00070                            avio_rb32(pb); /* Max buf size.  */
00071                            avio_rb32(pb); /* Max samples.  */
00072 
00073     thp->fps             = av_d2q(av_int2float(avio_rb32(pb)), INT_MAX);
00074     thp->framecnt        = avio_rb32(pb);
00075     thp->first_framesz   = avio_rb32(pb);
00076     pb->maxsize          = avio_rb32(pb);
00077     if(fsize>0 && (!pb->maxsize || fsize < pb->maxsize))
00078         pb->maxsize= fsize;
00079 
00080     thp->compoff         = avio_rb32(pb);
00081                            avio_rb32(pb); /* offsetDataOffset.  */
00082     thp->first_frame     = avio_rb32(pb);
00083     thp->last_frame      = avio_rb32(pb);
00084 
00085     thp->next_framesz    = thp->first_framesz;
00086     thp->next_frame      = thp->first_frame;
00087 
00088     /* Read the component structure.  */
00089     avio_seek (pb, thp->compoff, SEEK_SET);
00090     thp->compcount       = avio_rb32(pb);
00091 
00092     /* Read the list of component types.  */
00093     avio_read(pb, thp->components, 16);
00094 
00095     for (i = 0; i < thp->compcount; i++) {
00096         if (thp->components[i] == 0) {
00097             if (thp->vst != 0)
00098                 break;
00099 
00100             /* Video component.  */
00101             st = avformat_new_stream(s, NULL);
00102             if (!st)
00103                 return AVERROR(ENOMEM);
00104 
00105             /* The denominator and numerator are switched because 1/fps
00106                is required.  */
00107             avpriv_set_pts_info(st, 64, thp->fps.den, thp->fps.num);
00108             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00109             st->codec->codec_id = CODEC_ID_THP;
00110             st->codec->codec_tag = 0;  /* no fourcc */
00111             st->codec->width = avio_rb32(pb);
00112             st->codec->height = avio_rb32(pb);
00113             st->codec->sample_rate = av_q2d(thp->fps);
00114             thp->vst = st;
00115             thp->video_stream_index = st->index;
00116 
00117             if (thp->version == 0x11000)
00118                 avio_rb32(pb); /* Unknown.  */
00119         } else if (thp->components[i] == 1) {
00120             if (thp->has_audio != 0)
00121                 break;
00122 
00123             /* Audio component.  */
00124             st = avformat_new_stream(s, NULL);
00125             if (!st)
00126                 return AVERROR(ENOMEM);
00127 
00128             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00129             st->codec->codec_id = CODEC_ID_ADPCM_THP;
00130             st->codec->codec_tag = 0;  /* no fourcc */
00131             st->codec->channels    = avio_rb32(pb); /* numChannels.  */
00132             st->codec->sample_rate = avio_rb32(pb); /* Frequency.  */
00133 
00134             avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00135 
00136             thp->audio_stream_index = st->index;
00137             thp->has_audio = 1;
00138         }
00139     }
00140 
00141     return 0;
00142 }
00143 
00144 static int thp_read_packet(AVFormatContext *s,
00145                             AVPacket *pkt)
00146 {
00147     ThpDemuxContext *thp = s->priv_data;
00148     AVIOContext *pb = s->pb;
00149     unsigned int size;
00150     int ret;
00151 
00152     if (thp->audiosize == 0) {
00153         /* Terminate when last frame is reached.  */
00154         if (thp->frame >= thp->framecnt)
00155             return AVERROR(EIO);
00156 
00157         avio_seek(pb, thp->next_frame, SEEK_SET);
00158 
00159         /* Locate the next frame and read out its size.  */
00160         thp->next_frame += thp->next_framesz;
00161         thp->next_framesz = avio_rb32(pb);
00162 
00163                         avio_rb32(pb); /* Previous total size.  */
00164         size          = avio_rb32(pb); /* Total size of this frame.  */
00165 
00166         /* Store the audiosize so the next time this function is called,
00167            the audio can be read.  */
00168         if (thp->has_audio)
00169             thp->audiosize = avio_rb32(pb); /* Audio size.  */
00170         else
00171             thp->frame++;
00172 
00173         ret = av_get_packet(pb, pkt, size);
00174         if (ret != size) {
00175             av_free_packet(pkt);
00176             return AVERROR(EIO);
00177         }
00178 
00179         pkt->stream_index = thp->video_stream_index;
00180     } else {
00181         ret = av_get_packet(pb, pkt, thp->audiosize);
00182         if (ret != thp->audiosize) {
00183             av_free_packet(pkt);
00184             return AVERROR(EIO);
00185         }
00186 
00187         pkt->stream_index = thp->audio_stream_index;
00188         thp->audiosize = 0;
00189         thp->frame++;
00190     }
00191 
00192     return 0;
00193 }
00194 
00195 AVInputFormat ff_thp_demuxer = {
00196     .name           = "thp",
00197     .long_name      = NULL_IF_CONFIG_SMALL("THP"),
00198     .priv_data_size = sizeof(ThpDemuxContext),
00199     .read_probe     = thp_probe,
00200     .read_header    = thp_read_header,
00201     .read_packet    = thp_read_packet
00202 };