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wavpack: extract sample rate from the bitstream

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This way we don't require the caller to parse the block header. It also
allows the sample rate to change mid-stream.
This commit is contained in:
Anton Khirnov 2013-05-27 17:23:15 +02:00
parent 0ba49d28a1
commit 78f75b6fa4
1 changed files with 43 additions and 23 deletions
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66
libavcodec/wavpack.c
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@ -51,7 +51,7 @@
#define WV_FLT_ZERO_SIGN 0x10
enum WP_ID_Flags {
WP_IDF_MASK = 0x1F,
WP_IDF_MASK = 0x3F,
WP_IDF_IGNORE = 0x20,
WP_IDF_ODD = 0x40,
WP_IDF_LONG = 0x80
@ -71,7 +71,8 @@ enum WP_ID {
WP_ID_DATA,
WP_ID_CORR,
WP_ID_EXTRABITS,
WP_ID_CHANINFO
WP_ID_CHANINFO,
WP_ID_SAMPLE_RATE = 0x27,
};
typedef struct SavedContext {
@ -140,6 +141,11 @@ typedef struct WavpackContext {
int ch_offset;
} WavpackContext;
static const int wv_rates[16] = {
6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000,
32000, 44100, 48000, 64000, 88200, 96000, 192000, 0
};
// exponent table copied from WavPack source
static const uint8_t wp_exp2_table[256] = {
0x00, 0x01, 0x01, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x06, 0x07, 0x08, 0x08, 0x09, 0x0a, 0x0b,
@ -742,7 +748,7 @@ static av_cold int wavpack_decode_end(AVCodecContext *avctx)
}
static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
uint8_t **data, const uint8_t *buf, int buf_size)
AVFrame *frame, const uint8_t *buf, int buf_size)
{
WavpackContext *wc = avctx->priv_data;
WavpackFrameContext *s;
@ -752,7 +758,7 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
int got_terms = 0, got_weights = 0, got_samples = 0,
got_entropy = 0, got_bs = 0, got_float = 0, got_hybrid = 0;
int i, j, id, size, ssize, weights, t;
int bpp, chan, chmask, orig_bpp;
int bpp, chan, chmask, orig_bpp, sample_rate = 0;
if (block_no >= wc->fdec_num && wv_alloc_frame_context(wc) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error creating frame decode context\n");
@ -794,12 +800,6 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
s->hybrid_minclip = ((-1LL << (orig_bpp - 1)));
s->CRC = bytestream2_get_le32(&gb);
samples_l = data[wc->ch_offset];
if (s->stereo)
samples_r = data[wc->ch_offset + 1];
wc->ch_offset += 1 + s->stereo;
// parse metadata blocks
while (bytestream2_get_bytes_left(&gb)) {
id = bytestream2_get_byte(&gb);
@ -822,10 +822,6 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
"Block size %i is out of bounds\n", size);
break;
}
if (id & WP_IDF_IGNORE) {
bytestream2_skip(&gb, ssize);
continue;
}
switch (id & WP_IDF_MASK) {
case WP_ID_DECTERMS:
if (size > MAX_TERMS) {
@ -1053,6 +1049,13 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
if (!avctx->channel_layout)
avctx->channel_layout = chmask;
break;
case WP_ID_SAMPLE_RATE:
if (size != 3) {
av_log(avctx, AV_LOG_ERROR, "Invalid custom sample rate.\n");
return AVERROR_INVALIDDATA;
}
sample_rate = bytestream2_get_le24(&gb);
break;
default:
bytestream2_skip(&gb, size);
}
@ -1097,6 +1100,31 @@ static int wavpack_decode_block(AVCodecContext *avctx, int block_no,
}
}
if (!wc->ch_offset) {
int sr = (s->frame_flags >> 23) & 0xf;
if (sr == 0xf) {
if (!sample_rate) {
av_log(avctx, AV_LOG_ERROR, "Custom sample rate missing.\n");
return AVERROR_INVALIDDATA;
}
avctx->sample_rate = sample_rate;
} else
avctx->sample_rate = wv_rates[sr];
/* get output buffer */
frame->nb_samples = s->samples;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
}
samples_l = frame->extended_data[wc->ch_offset];
if (s->stereo)
samples_r = frame->extended_data[wc->ch_offset + 1];
wc->ch_offset += 1 + s->stereo;
if (s->stereo_in) {
ret = wv_unpack_stereo(s, &s->gb, samples_l, samples_r, avctx->sample_fmt);
if (ret < 0)
@ -1155,13 +1183,6 @@ static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
avctx->bits_per_raw_sample = ((frame_flags & 0x03) + 1) << 3;
}
/* get output buffer */
frame->nb_samples = s->samples;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
while (buf_size > 0) {
if (buf_size <= WV_HEADER_SIZE)
break;
@ -1176,8 +1197,7 @@ static int wavpack_decode_frame(AVCodecContext *avctx, void *data,
return AVERROR_INVALIDDATA;
}
if ((ret = wavpack_decode_block(avctx, s->block,
frame->extended_data,
buf, frame_size)) < 0) {
frame, buf, frame_size)) < 0) {
wavpack_decode_flush(avctx);
return ret;
}