Libav 0.7.1
libavformat/iff.c
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00001 /*
00002  * IFF (.iff) file demuxer
00003  * Copyright (c) 2008 Jaikrishnan Menon <realityman@gmx.net>
00004  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
00005  * Copyright (c) 2010 Sebastian Vater <cdgs.basty@googlemail.com>
00006  *
00007  * This file is part of Libav.
00008  *
00009  * Libav is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU Lesser General Public
00011  * License as published by the Free Software Foundation; either
00012  * version 2.1 of the License, or (at your option) any later version.
00013  *
00014  * Libav is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00017  * Lesser General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU Lesser General Public
00020  * License along with Libav; if not, write to the Free Software
00021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00022  */
00023 
00032 #include "libavutil/intreadwrite.h"
00033 #include "libavutil/dict.h"
00034 #include "avformat.h"
00035 
00036 #define ID_8SVX       MKTAG('8','S','V','X')
00037 #define ID_VHDR       MKTAG('V','H','D','R')
00038 #define ID_ATAK       MKTAG('A','T','A','K')
00039 #define ID_RLSE       MKTAG('R','L','S','E')
00040 #define ID_CHAN       MKTAG('C','H','A','N')
00041 #define ID_PBM        MKTAG('P','B','M',' ')
00042 #define ID_ILBM       MKTAG('I','L','B','M')
00043 #define ID_BMHD       MKTAG('B','M','H','D')
00044 #define ID_CMAP       MKTAG('C','M','A','P')
00045 
00046 #define ID_FORM       MKTAG('F','O','R','M')
00047 #define ID_ANNO       MKTAG('A','N','N','O')
00048 #define ID_AUTH       MKTAG('A','U','T','H')
00049 #define ID_CHRS       MKTAG('C','H','R','S')
00050 #define ID_COPYRIGHT  MKTAG('(','c',')',' ')
00051 #define ID_CSET       MKTAG('C','S','E','T')
00052 #define ID_FVER       MKTAG('F','V','E','R')
00053 #define ID_NAME       MKTAG('N','A','M','E')
00054 #define ID_TEXT       MKTAG('T','E','X','T')
00055 #define ID_BODY       MKTAG('B','O','D','Y')
00056 #define ID_ANNO       MKTAG('A','N','N','O')
00057 
00058 #define LEFT    2
00059 #define RIGHT   4
00060 #define STEREO  6
00061 
00062 #define PACKET_SIZE 1024
00063 
00064 typedef enum {
00065     COMP_NONE,
00066     COMP_FIB,
00067     COMP_EXP
00068 } svx8_compression_type;
00069 
00070 typedef enum {
00071     BITMAP_RAW,
00072     BITMAP_BYTERUN1
00073 } bitmap_compression_type;
00074 
00075 typedef struct {
00076     uint64_t  body_pos;
00077     uint32_t  body_size;
00078     uint32_t  sent_bytes;
00079     uint32_t  audio_frame_count;
00080 } IffDemuxContext;
00081 
00082 
00083 static void interleave_stereo(const uint8_t *src, uint8_t *dest, int size)
00084 {
00085     uint8_t *end = dest + size;
00086     size = size>>1;
00087 
00088     while(dest < end) {
00089         *dest++ = *src;
00090         *dest++ = *(src+size);
00091         src++;
00092     }
00093 }
00094 
00095 /* Metadata string read */
00096 static int get_metadata(AVFormatContext *s,
00097                         const char *const tag,
00098                         const unsigned data_size)
00099 {
00100     uint8_t *buf = ((data_size + 1) == 0) ? NULL : av_malloc(data_size + 1);
00101 
00102     if (!buf)
00103         return AVERROR(ENOMEM);
00104 
00105     if (avio_read(s->pb, buf, data_size) < 0) {
00106         av_free(buf);
00107         return AVERROR(EIO);
00108     }
00109     buf[data_size] = 0;
00110     av_dict_set(&s->metadata, tag, buf, AV_DICT_DONT_STRDUP_VAL);
00111     return 0;
00112 }
00113 
00114 static int iff_probe(AVProbeData *p)
00115 {
00116     const uint8_t *d = p->buf;
00117 
00118     if ( AV_RL32(d)   == ID_FORM &&
00119          (AV_RL32(d+8) == ID_8SVX || AV_RL32(d+8) == ID_PBM || AV_RL32(d+8) == ID_ILBM) )
00120         return AVPROBE_SCORE_MAX;
00121     return 0;
00122 }
00123 
00124 static int iff_read_header(AVFormatContext *s,
00125                            AVFormatParameters *ap)
00126 {
00127     IffDemuxContext *iff = s->priv_data;
00128     AVIOContext *pb = s->pb;
00129     AVStream *st;
00130     uint32_t chunk_id, data_size;
00131     int compression = -1;
00132 
00133     st = av_new_stream(s, 0);
00134     if (!st)
00135         return AVERROR(ENOMEM);
00136 
00137     st->codec->channels = 1;
00138     avio_skip(pb, 8);
00139     // codec_tag used by ByteRun1 decoder to distinguish progressive (PBM) and interlaced (ILBM) content
00140     st->codec->codec_tag = avio_rl32(pb);
00141 
00142     while(!pb->eof_reached) {
00143         uint64_t orig_pos;
00144         int res;
00145         const char *metadata_tag = NULL;
00146         chunk_id = avio_rl32(pb);
00147         data_size = avio_rb32(pb);
00148         orig_pos = avio_tell(pb);
00149 
00150         switch(chunk_id) {
00151         case ID_VHDR:
00152             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00153 
00154             if (data_size < 14)
00155                 return AVERROR_INVALIDDATA;
00156             avio_skip(pb, 12);
00157             st->codec->sample_rate = avio_rb16(pb);
00158             if (data_size >= 16) {
00159                 avio_skip(pb, 1);
00160                 compression        = avio_r8(pb);
00161             }
00162             break;
00163 
00164         case ID_BODY:
00165             iff->body_pos = avio_tell(pb);
00166             iff->body_size = data_size;
00167             break;
00168 
00169         case ID_CHAN:
00170             if (data_size < 4)
00171                 return AVERROR_INVALIDDATA;
00172             st->codec->channels = (avio_rb32(pb) < 6) ? 1 : 2;
00173             break;
00174 
00175         case ID_CMAP:
00176             st->codec->extradata_size = data_size;
00177             st->codec->extradata      = av_malloc(data_size);
00178             if (!st->codec->extradata)
00179                 return AVERROR(ENOMEM);
00180             if (avio_read(pb, st->codec->extradata, data_size) < 0)
00181                 return AVERROR(EIO);
00182             break;
00183 
00184         case ID_BMHD:
00185             st->codec->codec_type            = AVMEDIA_TYPE_VIDEO;
00186             if (data_size <= 8)
00187                 return AVERROR_INVALIDDATA;
00188             st->codec->width                 = avio_rb16(pb);
00189             st->codec->height                = avio_rb16(pb);
00190             avio_skip(pb, 4); // x, y offset
00191             st->codec->bits_per_coded_sample = avio_r8(pb);
00192             if (data_size >= 11) {
00193                 avio_skip(pb, 1); // masking
00194                 compression                  = avio_r8(pb);
00195             }
00196             if (data_size >= 16) {
00197                 avio_skip(pb, 3); // paddding, transparent
00198                 st->sample_aspect_ratio.num  = avio_r8(pb);
00199                 st->sample_aspect_ratio.den  = avio_r8(pb);
00200             }
00201             break;
00202 
00203         case ID_ANNO:
00204         case ID_TEXT:
00205             metadata_tag = "comment";
00206             break;
00207 
00208         case ID_AUTH:
00209             metadata_tag = "artist";
00210             break;
00211 
00212         case ID_COPYRIGHT:
00213             metadata_tag = "copyright";
00214             break;
00215 
00216         case ID_NAME:
00217             metadata_tag = "title";
00218             break;
00219         }
00220 
00221         if (metadata_tag) {
00222             if ((res = get_metadata(s, metadata_tag, data_size)) < 0) {
00223                 av_log(s, AV_LOG_ERROR, "cannot allocate metadata tag %s!", metadata_tag);
00224                 return res;
00225             }
00226         }
00227         avio_skip(pb, data_size - (avio_tell(pb) - orig_pos) + (data_size & 1));
00228     }
00229 
00230     avio_seek(pb, iff->body_pos, SEEK_SET);
00231 
00232     switch(st->codec->codec_type) {
00233     case AVMEDIA_TYPE_AUDIO:
00234         av_set_pts_info(st, 32, 1, st->codec->sample_rate);
00235 
00236         switch(compression) {
00237         case COMP_NONE:
00238             st->codec->codec_id = CODEC_ID_PCM_S8;
00239             break;
00240         case COMP_FIB:
00241             st->codec->codec_id = CODEC_ID_8SVX_FIB;
00242             break;
00243         case COMP_EXP:
00244             st->codec->codec_id = CODEC_ID_8SVX_EXP;
00245             break;
00246         default:
00247             av_log(s, AV_LOG_ERROR, "unknown compression method\n");
00248             return -1;
00249         }
00250 
00251         st->codec->bits_per_coded_sample = 8;
00252         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * st->codec->bits_per_coded_sample;
00253         st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00254         break;
00255 
00256     case AVMEDIA_TYPE_VIDEO:
00257         switch (compression) {
00258         case BITMAP_RAW:
00259             st->codec->codec_id = CODEC_ID_IFF_ILBM;
00260             break;
00261         case BITMAP_BYTERUN1:
00262             st->codec->codec_id = CODEC_ID_IFF_BYTERUN1;
00263             break;
00264         default:
00265             av_log(s, AV_LOG_ERROR, "unknown compression method\n");
00266             return AVERROR_INVALIDDATA;
00267         }
00268         break;
00269     default:
00270         return -1;
00271     }
00272 
00273     return 0;
00274 }
00275 
00276 static int iff_read_packet(AVFormatContext *s,
00277                            AVPacket *pkt)
00278 {
00279     IffDemuxContext *iff = s->priv_data;
00280     AVIOContext *pb = s->pb;
00281     AVStream *st = s->streams[0];
00282     int ret;
00283 
00284     if(iff->sent_bytes >= iff->body_size)
00285         return AVERROR(EIO);
00286 
00287     if(st->codec->channels == 2) {
00288         uint8_t sample_buffer[PACKET_SIZE];
00289 
00290         ret = avio_read(pb, sample_buffer, PACKET_SIZE);
00291         if(av_new_packet(pkt, PACKET_SIZE) < 0) {
00292             av_log(s, AV_LOG_ERROR, "cannot allocate packet\n");
00293             return AVERROR(ENOMEM);
00294         }
00295         interleave_stereo(sample_buffer, pkt->data, PACKET_SIZE);
00296     } else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00297         ret = av_get_packet(pb, pkt, iff->body_size);
00298     } else {
00299         ret = av_get_packet(pb, pkt, PACKET_SIZE);
00300     }
00301 
00302     if(iff->sent_bytes == 0)
00303         pkt->flags |= AV_PKT_FLAG_KEY;
00304 
00305     if(st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00306         iff->sent_bytes += PACKET_SIZE;
00307     } else {
00308         iff->sent_bytes = iff->body_size;
00309     }
00310     pkt->stream_index = 0;
00311     if(st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00312         pkt->pts = iff->audio_frame_count;
00313         iff->audio_frame_count += ret / st->codec->channels;
00314     }
00315     return ret;
00316 }
00317 
00318 AVInputFormat ff_iff_demuxer = {
00319     "IFF",
00320     NULL_IF_CONFIG_SMALL("IFF format"),
00321     sizeof(IffDemuxContext),
00322     iff_probe,
00323     iff_read_header,
00324     iff_read_packet,
00325 };