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shorten: use bytestream functions to decode the embedded WAVE header

This commit is contained in:
Justin Ruggles 2011-09-16 17:40:44 -04:00
parent c25762fcf1
commit 069ada46c1
1 changed files with 17 additions and 26 deletions
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43
libavcodec/shorten.c
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@ -28,6 +28,7 @@
#include <limits.h> #include <limits.h>
#include "avcodec.h" #include "avcodec.h"
#include "bytestream.h"
#include "get_bits.h" #include "get_bits.h"
#include "golomb.h" #include "golomb.h"
@ -191,47 +192,37 @@ static void init_offset(ShortenContext *s)
s->offset[chan][i] = mean; s->offset[chan][i] = mean;
} }
static inline int get_le32(GetBitContext *gb) static int decode_wave_header(AVCodecContext *avctx, const uint8_t *header,
int header_size)
{ {
return av_bswap32(get_bits_long(gb, 32));
}
static inline short get_le16(GetBitContext *gb)
{
return av_bswap16(get_bits_long(gb, 16));
}
static int decode_wave_header(AVCodecContext *avctx, uint8_t *header, int header_size)
{
GetBitContext hb;
int len; int len;
short wave_format; short wave_format;
init_get_bits(&hb, header, header_size*8);
if (get_le32(&hb) != MKTAG('R','I','F','F')) { if (bytestream_get_le32(&header) != MKTAG('R','I','F','F')) {
av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n"); av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");
return -1; return -1;
} }
skip_bits_long(&hb, 32); /* chunk_size */ header += 4; /* chunk size */;
if (get_le32(&hb) != MKTAG('W','A','V','E')) { if (bytestream_get_le32(&header) != MKTAG('W','A','V','E')) {
av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n"); av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n");
return -1; return -1;
} }
while (get_le32(&hb) != MKTAG('f','m','t',' ')) { while (bytestream_get_le32(&header) != MKTAG('f','m','t',' ')) {
len = get_le32(&hb); len = bytestream_get_le32(&header);
skip_bits(&hb, 8*len); header += len;
} }
len = get_le32(&hb); len = bytestream_get_le32(&header);
if (len < 16) { if (len < 16) {
av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n"); av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");
return -1; return -1;
} }
wave_format = get_le16(&hb); wave_format = bytestream_get_le16(&header);
switch (wave_format) { switch (wave_format) {
case WAVE_FORMAT_PCM: case WAVE_FORMAT_PCM:
@ -241,11 +232,11 @@ static int decode_wave_header(AVCodecContext *avctx, uint8_t *header, int header
return -1; return -1;
} }
skip_bits(&hb, 16); // skip channels (already got from shorten header) header += 2; // skip channels (already got from shorten header)
avctx->sample_rate = get_le32(&hb); avctx->sample_rate = bytestream_get_le32(&header);
skip_bits(&hb, 32); // skip bit rate (represents original uncompressed bit rate) header += 4; // skip bit rate (represents original uncompressed bit rate)
skip_bits(&hb, 16); // skip block align (not needed) header += 2; // skip block align (not needed)
avctx->bits_per_coded_sample = get_le16(&hb); avctx->bits_per_coded_sample = bytestream_get_le16(&header);
if (avctx->bits_per_coded_sample != 16) { if (avctx->bits_per_coded_sample != 16) {
av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n"); av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n");