riff: Move demuxing code to a separate file.

1 files changed, 229 insertions, 0 deletions

diff --git a/libavformat/riffdec.c b/libavformat/riffdec.c
new file mode 100644
index 0000000000..447a6864b7
--- /dev/null
+++ b/libavformat/riffdec.c
@@ -0,0 +1,229 @@
+/*
+ * RIFF demuxing functions and data
+ * Copyright (c) 2000 Fabrice Bellard
+ *
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/dict.h"
+#include "libavutil/error.h"
+#include "libavutil/log.h"
+#include "libavutil/mathematics.h"
+#include "libavcodec/avcodec.h"
+#include "libavcodec/bytestream.h"
+#include "avformat.h"
+#include "avio_internal.h"
+#include "riff.h"
+
+const AVCodecGuid ff_codec_wav_guids[] = {
+    { AV_CODEC_ID_AC3,      { 0x2C, 0x80, 0x6D, 0xE0, 0x46, 0xDB, 0xCF, 0x11, 0xB4, 0xD1, 0x00, 0x80, 0x5F, 0x6C, 0xBB, 0xEA } },
+    { AV_CODEC_ID_ATRAC3P,  { 0xBF, 0xAA, 0x23, 0xE9, 0x58, 0xCB, 0x71, 0x44, 0xA1, 0x19, 0xFF, 0xFA, 0x01, 0xE4, 0xCE, 0x62 } },
+    { AV_CODEC_ID_EAC3,     { 0xAF, 0x87, 0xFB, 0xA7, 0x02, 0x2D, 0xFB, 0x42, 0xA4, 0xD4, 0x05, 0xCD, 0x93, 0x84, 0x3B, 0xDD } },
+    { AV_CODEC_ID_MP2,      { 0x2B, 0x80, 0x6D, 0xE0, 0x46, 0xDB, 0xCF, 0x11, 0xB4, 0xD1, 0x00, 0x80, 0x5F, 0x6C, 0xBB, 0xEA } },
+    { AV_CODEC_ID_NONE }
+};
+
+enum AVCodecID ff_codec_guid_get_id(const AVCodecGuid *guids, ff_asf_guid guid)
+{
+    int i;
+    for (i = 0; guids[i].id != AV_CODEC_ID_NONE; i++)
+        if (!ff_guidcmp(guids[i].guid, guid))
+            return guids[i].id;
+    return AV_CODEC_ID_NONE;
+}
+
+/* We could be given one of the three possible structures here:
+ * WAVEFORMAT, PCMWAVEFORMAT or WAVEFORMATEX. Each structure
+ * is an expansion of the previous one with the fields added
+ * at the bottom. PCMWAVEFORMAT adds 'WORD wBitsPerSample' and
+ * WAVEFORMATEX adds 'WORD  cbSize' and basically makes itself
+ * an openended structure.
+ */
+
+static void parse_waveformatex(AVIOContext *pb, AVCodecContext *c)
+{
+    ff_asf_guid subformat;
+    c->bits_per_coded_sample = avio_rl16(pb);
+    c->channel_layout        = avio_rl32(pb); /* dwChannelMask */
+
+    ff_get_guid(pb, &subformat);
+    if (!memcmp(subformat + 4,
+                (const uint8_t[]){ FF_MEDIASUBTYPE_BASE_GUID }, 12)) {
+        c->codec_tag = AV_RL32(subformat);
+        c->codec_id  = ff_wav_codec_get_id(c->codec_tag,
+                                           c->bits_per_coded_sample);
+    } else {
+        c->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subformat);
+        if (!c->codec_id)
+            av_log(c, AV_LOG_WARNING,
+                   "unknown subformat:"FF_PRI_GUID"\n",
+                   FF_ARG_GUID(subformat));
+    }
+}
+
+int ff_get_wav_header(AVIOContext *pb, AVCodecContext *codec, int size)
+{
+    int id;
+
+    id                 = avio_rl16(pb);
+    codec->codec_type  = AVMEDIA_TYPE_AUDIO;
+    codec->channels    = avio_rl16(pb);
+    codec->sample_rate = avio_rl32(pb);
+    codec->bit_rate    = avio_rl32(pb) * 8;
+    codec->block_align = avio_rl16(pb);
+    if (size == 14) {  /* We're dealing with plain vanilla WAVEFORMAT */
+        codec->bits_per_coded_sample = 8;
+    } else
+        codec->bits_per_coded_sample = avio_rl16(pb);
+    if (id == 0xFFFE) {
+        codec->codec_tag = 0;
+    } else {
+        codec->codec_tag = id;
+        codec->codec_id  = ff_wav_codec_get_id(id,
+                                               codec->bits_per_coded_sample);
+    }
+    if (size >= 18) {  /* We're obviously dealing with WAVEFORMATEX */
+        int cbSize = avio_rl16(pb); /* cbSize */
+        size  -= 18;
+        cbSize = FFMIN(size, cbSize);
+        if (cbSize >= 22 && id == 0xfffe) { /* WAVEFORMATEXTENSIBLE */
+            parse_waveformatex(pb, codec);
+            cbSize -= 22;
+            size   -= 22;
+        }
+        codec->extradata_size = cbSize;
+        if (cbSize > 0) {
+            av_free(codec->extradata);
+            codec->extradata = av_mallocz(codec->extradata_size +
+                                          FF_INPUT_BUFFER_PADDING_SIZE);
+            if (!codec->extradata)
+                return AVERROR(ENOMEM);
+            avio_read(pb, codec->extradata, codec->extradata_size);
+            size -= cbSize;
+        }
+
+        /* It is possible for the chunk to contain garbage at the end */
+        if (size > 0)
+            avio_skip(pb, size);
+    }
+    if (codec->codec_id == AV_CODEC_ID_AAC_LATM) {
+        /* Channels and sample_rate values are those prior to applying SBR
+         * and/or PS. */
+        codec->channels    = 0;
+        codec->sample_rate = 0;
+    }
+    /* override bits_per_coded_sample for G.726 */
+    if (codec->codec_id == AV_CODEC_ID_ADPCM_G726)
+        codec->bits_per_coded_sample = codec->bit_rate / codec->sample_rate;
+
+    return 0;
+}
+
+enum AVCodecID ff_wav_codec_get_id(unsigned int tag, int bps)
+{
+    enum AVCodecID id;
+    id = ff_codec_get_id(ff_codec_wav_tags, tag);
+    if (id <= 0)
+        return id;
+
+    if (id == AV_CODEC_ID_PCM_S16LE)
+        id = ff_get_pcm_codec_id(bps, 0, 0, ~1);
+    else if (id == AV_CODEC_ID_PCM_F32LE)
+        id = ff_get_pcm_codec_id(bps, 1, 0,  0);
+
+    if (id == AV_CODEC_ID_ADPCM_IMA_WAV && bps == 8)
+        id = AV_CODEC_ID_PCM_ZORK;
+    return id;
+}
+
+int ff_get_bmp_header(AVIOContext *pb, AVStream *st)
+{
+    int tag1;
+    avio_rl32(pb); /* size */
+    st->codec->width  = avio_rl32(pb);
+    st->codec->height = (int32_t)avio_rl32(pb);
+    avio_rl16(pb); /* planes */
+    st->codec->bits_per_coded_sample = avio_rl16(pb); /* depth */
+    tag1                             = avio_rl32(pb);
+    avio_rl32(pb); /* ImageSize */
+    avio_rl32(pb); /* XPelsPerMeter */
+    avio_rl32(pb); /* YPelsPerMeter */
+    avio_rl32(pb); /* ClrUsed */
+    avio_rl32(pb); /* ClrImportant */
+    return tag1;
+}
+
+int ff_read_riff_info(AVFormatContext *s, int64_t size)
+{
+    int64_t start, end, cur;
+    AVIOContext *pb = s->pb;
+
+    start = avio_tell(pb);
+    end   = start + size;
+
+    while ((cur = avio_tell(pb)) >= 0 &&
+           cur <= end - 8 /* = tag + size */) {
+        uint32_t chunk_code;
+        int64_t chunk_size;
+        char key[5] = { 0 };
+        char *value;
+
+        chunk_code = avio_rl32(pb);
+        chunk_size = avio_rl32(pb);
+
+        if (chunk_size > end ||
+            end - chunk_size < cur ||
+            chunk_size == UINT_MAX) {
+            av_log(s, AV_LOG_WARNING, "too big INFO subchunk\n");
+            break;
+        }
+
+        chunk_size += (chunk_size & 1);
+
+        if (!chunk_code) {
+            if (chunk_size)
+                avio_skip(pb, chunk_size);
+            else if (pb->eof_reached) {
+                av_log(s, AV_LOG_WARNING, "truncated file\n");
+                return AVERROR_EOF;
+            }
+            continue;
+        }
+
+        value = av_malloc(chunk_size + 1);
+        if (!value) {
+            av_log(s, AV_LOG_ERROR,
+                   "out of memory, unable to read INFO tag\n");
+            return AVERROR(ENOMEM);
+        }
+
+        AV_WL32(key, chunk_code);
+
+        if (avio_read(pb, value, chunk_size) != chunk_size) {
+            av_free(value);
+            av_log(s, AV_LOG_WARNING,
+                   "premature end of file while reading INFO tag\n");
+            break;
+        }
+
+        value[chunk_size] = 0;
+
+        av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
+    }
+
+    return 0;
+}