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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 
00030 
00031 typedef struct CinFileHeader {
00032     int video_frame_size;
00033     int video_frame_width;
00034     int video_frame_height;
00035     int audio_frequency;
00036     int audio_bits;
00037     int audio_stereo;
00038     int audio_frame_size;
00039 } CinFileHeader;
00040 
00041 typedef struct CinFrameHeader {
00042     int audio_frame_type;
00043     int video_frame_type;
00044     int pal_colors_count;
00045     int audio_frame_size;
00046     int video_frame_size;
00047 } CinFrameHeader;
00048 
00049 typedef struct CinDemuxContext {
00050     int audio_stream_index;
00051     int video_stream_index;
00052     CinFileHeader file_header;
00053     int64_t audio_stream_pts;
00054     int64_t video_stream_pts;
00055     CinFrameHeader frame_header;
00056     int audio_buffer_size;
00057 } CinDemuxContext;
00058 
00059 
00060 static int cin_probe(AVProbeData *p)
00061 {
00062     /* header starts with this special marker */
00063     if (AV_RL32(&p->buf[0]) != 0x55AA0000)
00064         return 0;
00065 
00066     /* for accuracy, check some header field values */
00067     if (AV_RL32(&p->buf[12]) != 22050 || p->buf[16] != 16 || p->buf[17] != 0)
00068         return 0;
00069 
00070     return AVPROBE_SCORE_MAX;
00071 }
00072 
00073 static int cin_read_file_header(CinDemuxContext *cin, ByteIOContext *pb) {
00074     CinFileHeader *hdr = &cin->file_header;
00075 
00076     if (get_le32(pb) != 0x55AA0000)
00077         return AVERROR_INVALIDDATA;
00078 
00079     hdr->video_frame_size   = get_le32(pb);
00080     hdr->video_frame_width  = get_le16(pb);
00081     hdr->video_frame_height = get_le16(pb);
00082     hdr->audio_frequency    = get_le32(pb);
00083     hdr->audio_bits         = get_byte(pb);
00084     hdr->audio_stereo       = get_byte(pb);
00085     hdr->audio_frame_size   = get_le16(pb);
00086 
00087     if (hdr->audio_frequency != 22050 || hdr->audio_bits != 16 || hdr->audio_stereo != 0)
00088         return AVERROR_INVALIDDATA;
00089 
00090     return 0;
00091 }
00092 
00093 static int cin_read_header(AVFormatContext *s, AVFormatParameters *ap)
00094 {
00095     int rc;
00096     CinDemuxContext *cin = s->priv_data;
00097     CinFileHeader *hdr = &cin->file_header;
00098     ByteIOContext *pb = s->pb;
00099     AVStream *st;
00100 
00101     rc = cin_read_file_header(cin, pb);
00102     if (rc)
00103         return rc;
00104 
00105     cin->video_stream_pts = 0;
00106     cin->audio_stream_pts = 0;
00107     cin->audio_buffer_size = 0;
00108 
00109     /* initialize the video decoder stream */
00110     st = av_new_stream(s, 0);
00111     if (!st)
00112         return AVERROR(ENOMEM);
00113 
00114     av_set_pts_info(st, 32, 1, 12);
00115     cin->video_stream_index = st->index;
00116     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00117     st->codec->codec_id = CODEC_ID_DSICINVIDEO;
00118     st->codec->codec_tag = 0;  /* no fourcc */
00119     st->codec->width = hdr->video_frame_width;
00120     st->codec->height = hdr->video_frame_height;
00121 
00122     /* initialize the audio decoder stream */
00123     st = av_new_stream(s, 0);
00124     if (!st)
00125         return AVERROR(ENOMEM);
00126 
00127     av_set_pts_info(st, 32, 1, 22050);
00128     cin->audio_stream_index = st->index;
00129     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00130     st->codec->codec_id = CODEC_ID_DSICINAUDIO;
00131     st->codec->codec_tag = 0;  /* no tag */
00132     st->codec->channels = 1;
00133     st->codec->sample_rate = 22050;
00134     st->codec->bits_per_coded_sample = 16;
00135     st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;
00136     st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00137 
00138     return 0;
00139 }
00140 
00141 static int cin_read_frame_header(CinDemuxContext *cin, ByteIOContext *pb) {
00142     CinFrameHeader *hdr = &cin->frame_header;
00143 
00144     hdr->video_frame_type = get_byte(pb);
00145     hdr->audio_frame_type = get_byte(pb);
00146     hdr->pal_colors_count = get_le16(pb);
00147     hdr->video_frame_size = get_le32(pb);
00148     hdr->audio_frame_size = get_le32(pb);
00149 
00150     if (url_feof(pb) || url_ferror(pb))
00151         return AVERROR(EIO);
00152 
00153     if (get_le32(pb) != 0xAA55AA55)
00154         return AVERROR_INVALIDDATA;
00155 
00156     return 0;
00157 }
00158 
00159 static int cin_read_packet(AVFormatContext *s, AVPacket *pkt)
00160 {
00161     CinDemuxContext *cin = s->priv_data;
00162     ByteIOContext *pb = s->pb;
00163     CinFrameHeader *hdr = &cin->frame_header;
00164     int rc, palette_type, pkt_size;
00165     int ret;
00166 
00167     if (cin->audio_buffer_size == 0) {
00168         rc = cin_read_frame_header(cin, pb);
00169         if (rc)
00170             return rc;
00171 
00172         if ((int16_t)hdr->pal_colors_count < 0) {
00173             hdr->pal_colors_count = -(int16_t)hdr->pal_colors_count;
00174             palette_type = 1;
00175         } else {
00176             palette_type = 0;
00177         }
00178 
00179         /* palette and video packet */
00180         pkt_size = (palette_type + 3) * hdr->pal_colors_count + hdr->video_frame_size;
00181 
00182         ret = av_new_packet(pkt, 4 + pkt_size);
00183         if (ret < 0)
00184             return ret;
00185 
00186         pkt->stream_index = cin->video_stream_index;
00187         pkt->pts = cin->video_stream_pts++;
00188 
00189         pkt->data[0] = palette_type;
00190         pkt->data[1] = hdr->pal_colors_count & 0xFF;
00191         pkt->data[2] = hdr->pal_colors_count >> 8;
00192         pkt->data[3] = hdr->video_frame_type;
00193 
00194         ret = get_buffer(pb, &pkt->data[4], pkt_size);
00195         if (ret < 0) {
00196             av_free_packet(pkt);
00197             return ret;
00198         }
00199         if (ret < pkt_size)
00200             av_shrink_packet(pkt, 4 + ret);
00201 
00202         /* sound buffer will be processed on next read_packet() call */
00203         cin->audio_buffer_size = hdr->audio_frame_size;
00204         return 0;
00205     }
00206 
00207     /* audio packet */
00208     ret = av_get_packet(pb, pkt, cin->audio_buffer_size);
00209     if (ret < 0)
00210         return ret;
00211 
00212     pkt->stream_index = cin->audio_stream_index;
00213     pkt->pts = cin->audio_stream_pts;
00214     cin->audio_stream_pts += cin->audio_buffer_size * 2 / cin->file_header.audio_frame_size;
00215     cin->audio_buffer_size = 0;
00216     return 0;
00217 }
00218 
00219 AVInputFormat dsicin_demuxer = {
00220     "dsicin",
00221     NULL_IF_CONFIG_SMALL("Delphine Software International CIN format"),
00222     sizeof(CinDemuxContext),
00223     cin_probe,
00224     cin_read_header,
00225     cin_read_packet,
00226 };

Generated on Fri Sep 16 2011 17:17:48 for FFmpeg by  doxygen 1.7.1