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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 #include "internal.h"
00036 
00037 #define ID_8SVX       MKTAG('8','S','V','X')
00038 #define ID_VHDR       MKTAG('V','H','D','R')
00039 #define ID_ATAK       MKTAG('A','T','A','K')
00040 #define ID_RLSE       MKTAG('R','L','S','E')
00041 #define ID_CHAN       MKTAG('C','H','A','N')
00042 #define ID_PBM        MKTAG('P','B','M',' ')
00043 #define ID_ILBM       MKTAG('I','L','B','M')
00044 #define ID_BMHD       MKTAG('B','M','H','D')
00045 #define ID_CMAP       MKTAG('C','M','A','P')
00046 
00047 #define ID_FORM       MKTAG('F','O','R','M')
00048 #define ID_ANNO       MKTAG('A','N','N','O')
00049 #define ID_AUTH       MKTAG('A','U','T','H')
00050 #define ID_CHRS       MKTAG('C','H','R','S')
00051 #define ID_COPYRIGHT  MKTAG('(','c',')',' ')
00052 #define ID_CSET       MKTAG('C','S','E','T')
00053 #define ID_FVER       MKTAG('F','V','E','R')
00054 #define ID_NAME       MKTAG('N','A','M','E')
00055 #define ID_TEXT       MKTAG('T','E','X','T')
00056 #define ID_BODY       MKTAG('B','O','D','Y')
00057 #define ID_ANNO       MKTAG('A','N','N','O')
00058 
00059 #define LEFT    2
00060 #define RIGHT   4
00061 #define STEREO  6
00062 
00063 typedef enum {
00064     COMP_NONE,
00065     COMP_FIB,
00066     COMP_EXP
00067 } svx8_compression_type;
00068 
00069 typedef enum {
00070     BITMAP_RAW,
00071     BITMAP_BYTERUN1
00072 } bitmap_compression_type;
00073 
00074 typedef struct {
00075     uint64_t  body_pos;
00076     uint32_t  body_size;
00077     uint32_t  sent_bytes;
00078 } IffDemuxContext;
00079 
00080 
00081 /* Metadata string read */
00082 static int get_metadata(AVFormatContext *s,
00083                         const char *const tag,
00084                         const unsigned data_size)
00085 {
00086     uint8_t *buf = ((data_size + 1) == 0) ? NULL : av_malloc(data_size + 1);
00087 
00088     if (!buf)
00089         return AVERROR(ENOMEM);
00090 
00091     if (avio_read(s->pb, buf, data_size) < 0) {
00092         av_free(buf);
00093         return AVERROR(EIO);
00094     }
00095     buf[data_size] = 0;
00096     av_dict_set(&s->metadata, tag, buf, AV_DICT_DONT_STRDUP_VAL);
00097     return 0;
00098 }
00099 
00100 static int iff_probe(AVProbeData *p)
00101 {
00102     const uint8_t *d = p->buf;
00103 
00104     if ( AV_RL32(d)   == ID_FORM &&
00105          (AV_RL32(d+8) == ID_8SVX || AV_RL32(d+8) == ID_PBM || AV_RL32(d+8) == ID_ILBM) )
00106         return AVPROBE_SCORE_MAX;
00107     return 0;
00108 }
00109 
00110 static int iff_read_header(AVFormatContext *s,
00111                            AVFormatParameters *ap)
00112 {
00113     IffDemuxContext *iff = s->priv_data;
00114     AVIOContext *pb = s->pb;
00115     AVStream *st;
00116     uint32_t chunk_id, data_size;
00117     int compression = -1;
00118 
00119     st = avformat_new_stream(s, NULL);
00120     if (!st)
00121         return AVERROR(ENOMEM);
00122 
00123     st->codec->channels = 1;
00124     avio_skip(pb, 8);
00125     // codec_tag used by ByteRun1 decoder to distinguish progressive (PBM) and interlaced (ILBM) content
00126     st->codec->codec_tag = avio_rl32(pb);
00127 
00128     while(!pb->eof_reached) {
00129         uint64_t orig_pos;
00130         int res;
00131         const char *metadata_tag = NULL;
00132         chunk_id = avio_rl32(pb);
00133         data_size = avio_rb32(pb);
00134         orig_pos = avio_tell(pb);
00135 
00136         switch(chunk_id) {
00137         case ID_VHDR:
00138             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00139 
00140             if (data_size < 14)
00141                 return AVERROR_INVALIDDATA;
00142             avio_skip(pb, 12);
00143             st->codec->sample_rate = avio_rb16(pb);
00144             if (data_size >= 16) {
00145                 avio_skip(pb, 1);
00146                 compression        = avio_r8(pb);
00147             }
00148             break;
00149 
00150         case ID_BODY:
00151             iff->body_pos = avio_tell(pb);
00152             iff->body_size = data_size;
00153             break;
00154 
00155         case ID_CHAN:
00156             if (data_size < 4)
00157                 return AVERROR_INVALIDDATA;
00158             st->codec->channels = (avio_rb32(pb) < 6) ? 1 : 2;
00159             break;
00160 
00161         case ID_CMAP:
00162             st->codec->extradata_size = data_size;
00163             st->codec->extradata      = av_malloc(data_size);
00164             if (!st->codec->extradata)
00165                 return AVERROR(ENOMEM);
00166             if (avio_read(pb, st->codec->extradata, data_size) < 0)
00167                 return AVERROR(EIO);
00168             break;
00169 
00170         case ID_BMHD:
00171             st->codec->codec_type            = AVMEDIA_TYPE_VIDEO;
00172             if (data_size <= 8)
00173                 return AVERROR_INVALIDDATA;
00174             st->codec->width                 = avio_rb16(pb);
00175             st->codec->height                = avio_rb16(pb);
00176             avio_skip(pb, 4); // x, y offset
00177             st->codec->bits_per_coded_sample = avio_r8(pb);
00178             if (data_size >= 11) {
00179                 avio_skip(pb, 1); // masking
00180                 compression                  = avio_r8(pb);
00181             }
00182             if (data_size >= 16) {
00183                 avio_skip(pb, 3); // paddding, transparent
00184                 st->sample_aspect_ratio.num  = avio_r8(pb);
00185                 st->sample_aspect_ratio.den  = avio_r8(pb);
00186             }
00187             break;
00188 
00189         case ID_ANNO:
00190         case ID_TEXT:
00191             metadata_tag = "comment";
00192             break;
00193 
00194         case ID_AUTH:
00195             metadata_tag = "artist";
00196             break;
00197 
00198         case ID_COPYRIGHT:
00199             metadata_tag = "copyright";
00200             break;
00201 
00202         case ID_NAME:
00203             metadata_tag = "title";
00204             break;
00205         }
00206 
00207         if (metadata_tag) {
00208             if ((res = get_metadata(s, metadata_tag, data_size)) < 0) {
00209                 av_log(s, AV_LOG_ERROR, "cannot allocate metadata tag %s!", metadata_tag);
00210                 return res;
00211             }
00212         }
00213         avio_skip(pb, data_size - (avio_tell(pb) - orig_pos) + (data_size & 1));
00214     }
00215 
00216     avio_seek(pb, iff->body_pos, SEEK_SET);
00217 
00218     switch(st->codec->codec_type) {
00219     case AVMEDIA_TYPE_AUDIO:
00220         avpriv_set_pts_info(st, 32, 1, st->codec->sample_rate);
00221 
00222         switch(compression) {
00223         case COMP_NONE:
00224             st->codec->codec_id = CODEC_ID_PCM_S8_PLANAR;
00225             break;
00226         case COMP_FIB:
00227             st->codec->codec_id = CODEC_ID_8SVX_FIB;
00228             break;
00229         case COMP_EXP:
00230             st->codec->codec_id = CODEC_ID_8SVX_EXP;
00231             break;
00232         default:
00233             av_log(s, AV_LOG_ERROR, "unknown compression method\n");
00234             return -1;
00235         }
00236 
00237         st->codec->bits_per_coded_sample = 8;
00238         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * st->codec->bits_per_coded_sample;
00239         st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00240         break;
00241 
00242     case AVMEDIA_TYPE_VIDEO:
00243         switch (compression) {
00244         case BITMAP_RAW:
00245             st->codec->codec_id = CODEC_ID_IFF_ILBM;
00246             break;
00247         case BITMAP_BYTERUN1:
00248             st->codec->codec_id = CODEC_ID_IFF_BYTERUN1;
00249             break;
00250         default:
00251             av_log(s, AV_LOG_ERROR, "unknown compression method\n");
00252             return AVERROR_INVALIDDATA;
00253         }
00254         break;
00255     default:
00256         return -1;
00257     }
00258 
00259     return 0;
00260 }
00261 
00262 static int iff_read_packet(AVFormatContext *s,
00263                            AVPacket *pkt)
00264 {
00265     IffDemuxContext *iff = s->priv_data;
00266     AVIOContext *pb = s->pb;
00267     int ret;
00268 
00269     if(iff->sent_bytes >= iff->body_size)
00270         return AVERROR_EOF;
00271 
00272     ret = av_get_packet(pb, pkt, iff->body_size);
00273     if (ret < 0)
00274         return ret;
00275 
00276     if(iff->sent_bytes == 0)
00277         pkt->flags |= AV_PKT_FLAG_KEY;
00278     iff->sent_bytes = iff->body_size;
00279 
00280     pkt->stream_index = 0;
00281     return ret;
00282 }
00283 
00284 AVInputFormat ff_iff_demuxer = {
00285     .name           = "IFF",
00286     .long_name      = NULL_IF_CONFIG_SMALL("IFF format"),
00287     .priv_data_size = sizeof(IffDemuxContext),
00288     .read_probe     = iff_probe,
00289     .read_header    = iff_read_header,
00290     .read_packet    = iff_read_packet,
00291 };
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