2 * RIFF demuxing functions and data
3 * Copyright (c) 2000 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/dict.h"
23 #include "libavutil/error.h"
24 #include "libavutil/log.h"
25 #include "libavutil/mathematics.h"
26 #include "libavcodec/avcodec.h"
27 #include "libavcodec/bytestream.h"
29 #include "avio_internal.h"
32 void ff_get_guid(AVIOContext *s, ff_asf_guid *g)
34 av_assert0(sizeof(*g) == 16); //compiler will optimize this out
35 if (avio_read(s, *g, sizeof(*g)) < (int)sizeof(*g))
36 memset(*g, 0, sizeof(*g));
39 enum AVCodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
42 for (i = 0; guids[i].id != AV_CODEC_ID_NONE; i++)
43 if (!ff_guidcmp(guids[i].guid, guid))
45 return AV_CODEC_ID_NONE;
48 /* We could be given one of the three possible structures here:
49 * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure
50 * is an expansion of the previous one with the fields added
51 * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and
52 * WAVEFORMATEX adds 'WORD cbSize' and basically makes itself
53 * an openended structure.
56 static void parse_waveformatex(AVIOContext *pb, AVCodecContext *c)
58 ff_asf_guid subformat;
59 int bps = avio_rl16(pb);
61 c->bits_per_coded_sample = bps;
63 c->channel_layout = avio_rl32(pb); /* dwChannelMask */
65 ff_get_guid(pb, &subformat);
66 if (!memcmp(subformat + 4,
67 (const uint8_t[]){ FF_MEDIASUBTYPE_BASE_GUID }, 12)) {
68 c->codec_tag = AV_RL32(subformat);
69 c->codec_id = ff_wav_codec_get_id(c->codec_tag,
70 c->bits_per_coded_sample);
72 c->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subformat);
74 av_log(c, AV_LOG_WARNING,
75 "unknown subformat:"FF_PRI_GUID"\n",
76 FF_ARG_GUID(subformat));
80 int ff_get_wav_header(AVIOContext *pb, AVCodecContext *codec, int size)
85 codec->codec_type = AVMEDIA_TYPE_AUDIO;
86 codec->channels = avio_rl16(pb);
87 codec->sample_rate = avio_rl32(pb);
88 codec->bit_rate = avio_rl32(pb) * 8;
89 codec->block_align = avio_rl16(pb);
90 if (size == 14) { /* We're dealing with plain vanilla WAVEFORMAT */
91 codec->bits_per_coded_sample = 8;
93 codec->bits_per_coded_sample = avio_rl16(pb);
97 codec->codec_tag = id;
98 codec->codec_id = ff_wav_codec_get_id(id,
99 codec->bits_per_coded_sample);
101 if (size >= 18) { /* We're obviously dealing with WAVEFORMATEX */
102 int cbSize = avio_rl16(pb); /* cbSize */
104 cbSize = FFMIN(size, cbSize);
105 if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */
106 parse_waveformatex(pb, codec);
111 av_free(codec->extradata);
112 if (ff_get_extradata(codec, pb, cbSize) < 0)
113 return AVERROR(ENOMEM);
117 /* It is possible for the chunk to contain garbage at the end */
121 if (codec->sample_rate <= 0) {
122 av_log(NULL, AV_LOG_ERROR,
123 "Invalid sample rate: %d\n", codec->sample_rate);
124 return AVERROR_INVALIDDATA;
126 if (codec->codec_id == AV_CODEC_ID_AAC_LATM) {
127 /* Channels and sample_rate values are those prior to applying SBR
130 codec->sample_rate = 0;
132 /* override bits_per_coded_sample for G.726 */
133 if (codec->codec_id == AV_CODEC_ID_ADPCM_G726 && codec->sample_rate)
134 codec->bits_per_coded_sample = codec->bit_rate / codec->sample_rate;
139 enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
142 id = ff_codec_get_id(ff_codec_wav_tags, tag);
146 if (id == AV_CODEC_ID_PCM_S16LE)
147 id = ff_get_pcm_codec_id(bps, 0, 0, ~1);
148 else if (id == AV_CODEC_ID_PCM_F32LE)
149 id = ff_get_pcm_codec_id(bps, 1, 0, 0);
151 if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
152 id = AV_CODEC_ID_PCM_ZORK;
156 int ff_get_bmp_header(AVIOContext *pb, AVStream *st, unsigned *esize)
159 if(esize) *esize = avio_rl32(pb);
161 st->codec->width = avio_rl32(pb);
162 st->codec->height = (int32_t)avio_rl32(pb);
163 avio_rl16(pb); /* planes */
164 st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */
165 tag1 = avio_rl32(pb);
166 avio_rl32(pb); /* ImageSize */
167 avio_rl32(pb); /* XPelsPerMeter */
168 avio_rl32(pb); /* YPelsPerMeter */
169 avio_rl32(pb); /* ClrUsed */
170 avio_rl32(pb); /* ClrImportant */
174 int ff_read_riff_info(AVFormatContext *s, int64_t size)
176 int64_t start, end, cur;
177 AVIOContext *pb = s->pb;
179 start = avio_tell(pb);
182 while ((cur = avio_tell(pb)) >= 0 &&
183 cur <= end - 8 /* = tag + size */) {
189 chunk_code = avio_rl32(pb);
190 chunk_size = avio_rl32(pb);
192 if (chunk_code || chunk_size) {
193 av_log(s, AV_LOG_WARNING, "INFO subchunk truncated\n");
194 return AVERROR_INVALIDDATA;
198 if (chunk_size > end ||
199 end - chunk_size < cur ||
200 chunk_size == UINT_MAX) {
201 avio_seek(pb, -9, SEEK_CUR);
202 chunk_code = avio_rl32(pb);
203 chunk_size = avio_rl32(pb);
204 if (chunk_size > end || end - chunk_size < cur || chunk_size == UINT_MAX) {
205 av_log(s, AV_LOG_WARNING, "too big INFO subchunk\n");
206 return AVERROR_INVALIDDATA;
210 chunk_size += (chunk_size & 1);
214 avio_skip(pb, chunk_size);
215 else if (pb->eof_reached) {
216 av_log(s, AV_LOG_WARNING, "truncated file\n");
222 value = av_mallocz(chunk_size + 1);
224 av_log(s, AV_LOG_ERROR,
225 "out of memory, unable to read INFO tag\n");
226 return AVERROR(ENOMEM);
229 AV_WL32(key, chunk_code);
231 if (avio_read(pb, value, chunk_size) != chunk_size) {
232 av_log(s, AV_LOG_WARNING,
233 "premature end of file while reading INFO tag\n");
236 av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);