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libavformat/dsicin.c

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00001 /*
00002  * Delphine Software International CIN File Demuxer
00003  * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
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 
00027 #include "libavutil/intreadwrite.h"
00028 #include "avformat.h"
00029 #include "internal.h"
00030 #include "avio_internal.h"
00031 
00032 
00033 typedef struct CinFileHeader {
00034     int video_frame_size;
00035     int video_frame_width;
00036     int video_frame_height;
00037     int audio_frequency;
00038     int audio_bits;
00039     int audio_stereo;
00040     int audio_frame_size;
00041 } CinFileHeader;
00042 
00043 typedef struct CinFrameHeader {
00044     int audio_frame_type;
00045     int video_frame_type;
00046     int pal_colors_count;
00047     int audio_frame_size;
00048     int video_frame_size;
00049 } CinFrameHeader;
00050 
00051 typedef struct CinDemuxContext {
00052     int audio_stream_index;
00053     int video_stream_index;
00054     CinFileHeader file_header;
00055     int64_t audio_stream_pts;
00056     int64_t video_stream_pts;
00057     CinFrameHeader frame_header;
00058     int audio_buffer_size;
00059 } CinDemuxContext;
00060 
00061 
00062 static int cin_probe(AVProbeData *p)
00063 {
00064     /* header starts with this special marker */
00065     if (AV_RL32(&p->buf[0]) != 0x55AA0000)
00066         return 0;
00067 
00068     /* for accuracy, check some header field values */
00069     if (AV_RL32(&p->buf[12]) != 22050 || p->buf[16] != 16 || p->buf[17] != 0)
00070         return 0;
00071 
00072     return AVPROBE_SCORE_MAX;
00073 }
00074 
00075 static int cin_read_file_header(CinDemuxContext *cin, AVIOContext *pb) {
00076     CinFileHeader *hdr = &cin->file_header;
00077 
00078     if (avio_rl32(pb) != 0x55AA0000)
00079         return AVERROR_INVALIDDATA;
00080 
00081     hdr->video_frame_size   = avio_rl32(pb);
00082     hdr->video_frame_width  = avio_rl16(pb);
00083     hdr->video_frame_height = avio_rl16(pb);
00084     hdr->audio_frequency    = avio_rl32(pb);
00085     hdr->audio_bits         = avio_r8(pb);
00086     hdr->audio_stereo       = avio_r8(pb);
00087     hdr->audio_frame_size   = avio_rl16(pb);
00088 
00089     if (hdr->audio_frequency != 22050 || hdr->audio_bits != 16 || hdr->audio_stereo != 0)
00090         return AVERROR_INVALIDDATA;
00091 
00092     return 0;
00093 }
00094 
00095 static int cin_read_header(AVFormatContext *s, AVFormatParameters *ap)
00096 {
00097     int rc;
00098     CinDemuxContext *cin = s->priv_data;
00099     CinFileHeader *hdr = &cin->file_header;
00100     AVIOContext *pb = s->pb;
00101     AVStream *st;
00102 
00103     rc = cin_read_file_header(cin, pb);
00104     if (rc)
00105         return rc;
00106 
00107     cin->video_stream_pts = 0;
00108     cin->audio_stream_pts = 0;
00109     cin->audio_buffer_size = 0;
00110 
00111     /* initialize the video decoder stream */
00112     st = avformat_new_stream(s, NULL);
00113     if (!st)
00114         return AVERROR(ENOMEM);
00115 
00116     avpriv_set_pts_info(st, 32, 1, 12);
00117     cin->video_stream_index = st->index;
00118     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00119     st->codec->codec_id = CODEC_ID_DSICINVIDEO;
00120     st->codec->codec_tag = 0;  /* no fourcc */
00121     st->codec->width = hdr->video_frame_width;
00122     st->codec->height = hdr->video_frame_height;
00123 
00124     /* initialize the audio decoder stream */
00125     st = avformat_new_stream(s, NULL);
00126     if (!st)
00127         return AVERROR(ENOMEM);
00128 
00129     avpriv_set_pts_info(st, 32, 1, 22050);
00130     cin->audio_stream_index = st->index;
00131     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00132     st->codec->codec_id = CODEC_ID_DSICINAUDIO;
00133     st->codec->codec_tag = 0;  /* no tag */
00134     st->codec->channels = 1;
00135     st->codec->sample_rate = 22050;
00136     st->codec->bits_per_coded_sample = 8;
00137     st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;
00138 
00139     return 0;
00140 }
00141 
00142 static int cin_read_frame_header(CinDemuxContext *cin, AVIOContext *pb) {
00143     CinFrameHeader *hdr = &cin->frame_header;
00144 
00145     hdr->video_frame_type = avio_r8(pb);
00146     hdr->audio_frame_type = avio_r8(pb);
00147     hdr->pal_colors_count = avio_rl16(pb);
00148     hdr->video_frame_size = avio_rl32(pb);
00149     hdr->audio_frame_size = avio_rl32(pb);
00150 
00151     if (url_feof(pb) || pb->error)
00152         return AVERROR(EIO);
00153 
00154     if (avio_rl32(pb) != 0xAA55AA55)
00155         return AVERROR_INVALIDDATA;
00156 
00157     return 0;
00158 }
00159 
00160 static int cin_read_packet(AVFormatContext *s, AVPacket *pkt)
00161 {
00162     CinDemuxContext *cin = s->priv_data;
00163     AVIOContext *pb = s->pb;
00164     CinFrameHeader *hdr = &cin->frame_header;
00165     int rc, palette_type, pkt_size;
00166     int ret;
00167 
00168     if (cin->audio_buffer_size == 0) {
00169         rc = cin_read_frame_header(cin, pb);
00170         if (rc)
00171             return rc;
00172 
00173         if ((int16_t)hdr->pal_colors_count < 0) {
00174             hdr->pal_colors_count = -(int16_t)hdr->pal_colors_count;
00175             palette_type = 1;
00176         } else {
00177             palette_type = 0;
00178         }
00179 
00180         /* palette and video packet */
00181         pkt_size = (palette_type + 3) * hdr->pal_colors_count + hdr->video_frame_size;
00182 
00183         pkt_size = ffio_limit(pb, pkt_size);
00184 
00185         ret = av_new_packet(pkt, 4 + pkt_size);
00186         if (ret < 0)
00187             return ret;
00188 
00189         pkt->stream_index = cin->video_stream_index;
00190         pkt->pts = cin->video_stream_pts++;
00191 
00192         pkt->data[0] = palette_type;
00193         pkt->data[1] = hdr->pal_colors_count & 0xFF;
00194         pkt->data[2] = hdr->pal_colors_count >> 8;
00195         pkt->data[3] = hdr->video_frame_type;
00196 
00197         ret = avio_read(pb, &pkt->data[4], pkt_size);
00198         if (ret < 0) {
00199             av_free_packet(pkt);
00200             return ret;
00201         }
00202         if (ret < pkt_size)
00203             av_shrink_packet(pkt, 4 + ret);
00204 
00205         /* sound buffer will be processed on next read_packet() call */
00206         cin->audio_buffer_size = hdr->audio_frame_size;
00207         return 0;
00208     }
00209 
00210     /* audio packet */
00211     ret = av_get_packet(pb, pkt, cin->audio_buffer_size);
00212     if (ret < 0)
00213         return ret;
00214 
00215     pkt->stream_index = cin->audio_stream_index;
00216     pkt->pts = cin->audio_stream_pts;
00217     pkt->duration = cin->audio_buffer_size - (pkt->pts == 0);
00218     cin->audio_stream_pts += pkt->duration;
00219     cin->audio_buffer_size = 0;
00220     return 0;
00221 }
00222 
00223 AVInputFormat ff_dsicin_demuxer = {
00224     .name           = "dsicin",
00225     .long_name      = NULL_IF_CONFIG_SMALL("Delphine Software International CIN format"),
00226     .priv_data_size = sizeof(CinDemuxContext),
00227     .read_probe     = cin_probe,
00228     .read_header    = cin_read_header,
00229     .read_packet    = cin_read_packet,
00230 };
Generated on Fri Feb 1 2013 14:34:51 for FFmpeg by doxygen 1.7.1