* FLAC (Free Lossless Audio Codec) decoder
* Copyright (c) 2003 Alex Beregszaszi
*
- * This library is free software; you can redistribute it and/or
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * FFmpeg 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 this library; if not, write to the Free Software
+ * License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <limits.h>
+#define ALT_BITSTREAM_READER
#include "avcodec.h"
#include "bitstream.h"
#include "golomb.h"
256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
};
-static int64_t get_utf8(GetBitContext *gb)
-{
- uint64_t val;
- int ones=0, bytes;
-
- while(get_bits1(gb))
- ones++;
-
- if (ones==0) bytes=0;
- else if(ones==1) return -1;
- else bytes= ones - 1;
-
- val= get_bits(gb, 7-ones);
- while(bytes--){
- const int tmp = get_bits(gb, 8);
-
- if((tmp>>6) != 2)
- return -1;
- val<<=6;
- val|= tmp&0x3F;
- }
+static int64_t get_utf8(GetBitContext *gb){
+ int64_t val;
+ GET_UTF8(val, get_bits(gb, 8), return -1;)
return val;
}
-#if 0
-static int skip_utf8(GetBitContext *gb)
-{
- int ones=0, bytes;
-
- while(get_bits1(gb))
- ones++;
-
- if (ones==0) bytes=0;
- else if(ones==1) return -1;
- else bytes= ones - 1;
-
- skip_bits(gb, 7-ones);
- while(bytes--){
- const int tmp = get_bits(gb, 8);
-
- if((tmp>>6) != 2)
- return -1;
- }
- return 0;
-}
-#endif
-
static void metadata_streaminfo(FLACContext *s);
-static void dump_headers(FLACContext *s);
+static void allocate_buffers(FLACContext *s);
+static int metadata_parse(FLACContext *s);
-static int flac_decode_init(AVCodecContext * avctx)
+static av_cold int flac_decode_init(AVCodecContext * avctx)
{
FLACContext *s = avctx->priv_data;
s->avctx = avctx;
- /* initialize based on the demuxer-supplied streamdata header */
- if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
+ if (avctx->extradata_size > 4) {
+ /* initialize based on the demuxer-supplied streamdata header */
init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);
- metadata_streaminfo(s);
- dump_headers(s);
+ if (avctx->extradata_size == FLAC_STREAMINFO_SIZE) {
+ metadata_streaminfo(s);
+ allocate_buffers(s);
+ } else {
+ metadata_parse(s);
+ }
}
return 0;
skip_bits(&s->gb, 64); /* md5 sum */
skip_bits(&s->gb, 64); /* md5 sum */
- allocate_buffers(s);
+ dump_headers(s);
+}
+
+/**
+ * Parse a list of metadata blocks. This list of blocks must begin with
+ * the fLaC marker.
+ * @param s the flac decoding context containing the gb bit reader used to
+ * parse metadata
+ * @return 1 if some metadata was read, 0 if no fLaC marker was found
+ */
+static int metadata_parse(FLACContext *s)
+{
+ int i, metadata_last, metadata_type, metadata_size, streaminfo_updated=0;
+
+ if (show_bits_long(&s->gb, 32) == MKBETAG('f','L','a','C')) {
+ skip_bits(&s->gb, 32);
+
+ av_log(s->avctx, AV_LOG_DEBUG, "STREAM HEADER\n");
+ do {
+ metadata_last = get_bits1(&s->gb);
+ metadata_type = get_bits(&s->gb, 7);
+ metadata_size = get_bits_long(&s->gb, 24);
+
+ av_log(s->avctx, AV_LOG_DEBUG,
+ " metadata block: flag = %d, type = %d, size = %d\n",
+ metadata_last, metadata_type, metadata_size);
+ if (metadata_size) {
+ switch (metadata_type) {
+ case METADATA_TYPE_STREAMINFO:
+ metadata_streaminfo(s);
+ streaminfo_updated = 1;
+ break;
+
+ default:
+ for (i=0; i<metadata_size; i++)
+ skip_bits(&s->gb, 8);
+ }
+ }
+ } while (!metadata_last);
+
+ if (streaminfo_updated)
+ allocate_buffers(s);
+ return 1;
+ }
+ return 0;
}
static int decode_residuals(FLACContext *s, int channel, int pred_order)
int sample = 0, samples;
method_type = get_bits(&s->gb, 2);
- if (method_type != 0){
+ if (method_type > 1){
av_log(s->avctx, AV_LOG_DEBUG, "illegal residual coding method %d\n", method_type);
return -1;
}
rice_order = get_bits(&s->gb, 4);
samples= s->blocksize >> rice_order;
+ if (pred_order > samples) {
+ av_log(s->avctx, AV_LOG_ERROR, "invalid predictor order: %i > %i\n", pred_order, samples);
+ return -1;
+ }
sample=
i= pred_order;
for (partition = 0; partition < (1 << rice_order); partition++)
{
- tmp = get_bits(&s->gb, 4);
- if (tmp == 15)
+ tmp = get_bits(&s->gb, method_type == 0 ? 4 : 5);
+ if (tmp == (method_type == 0 ? 15 : 31))
{
av_log(s->avctx, AV_LOG_DEBUG, "fixed len partition\n");
tmp = get_bits(&s->gb, 5);
static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order)
{
- int i;
+ const int blocksize = s->blocksize;
+ int32_t *decoded = s->decoded[channel];
+ int a, b, c, d, i;
// av_log(s->avctx, AV_LOG_DEBUG, " SUBFRAME FIXED\n");
for (i = 0; i < pred_order; i++)
{
- s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
+ decoded[i] = get_sbits(&s->gb, s->curr_bps);
// av_log(s->avctx, AV_LOG_DEBUG, " %d: %d\n", i, s->decoded[channel][i]);
}
if (decode_residuals(s, channel, pred_order) < 0)
return -1;
+ a = decoded[pred_order-1];
+ b = a - decoded[pred_order-2];
+ c = b - decoded[pred_order-2] + decoded[pred_order-3];
+ d = c - decoded[pred_order-2] + 2*decoded[pred_order-3] - decoded[pred_order-4];
+
switch(pred_order)
{
case 0:
break;
case 1:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] += s->decoded[channel][i-1];
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += decoded[i];
break;
case 2:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] += 2*s->decoded[channel][i-1]
- - s->decoded[channel][i-2];
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += decoded[i];
break;
case 3:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] += 3*s->decoded[channel][i-1]
- - 3*s->decoded[channel][i-2]
- + s->decoded[channel][i-3];
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += c += decoded[i];
break;
case 4:
- for (i = pred_order; i < s->blocksize; i++)
- s->decoded[channel][i] += 4*s->decoded[channel][i-1]
- - 6*s->decoded[channel][i-2]
- + 4*s->decoded[channel][i-3]
- - s->decoded[channel][i-4];
+ for (i = pred_order; i < blocksize; i++)
+ decoded[i] = a += b += c += d += decoded[i];
break;
default:
av_log(s->avctx, AV_LOG_ERROR, "illegal pred order %d\n", pred_order);
static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order)
{
- int sum, i, j;
+ int i, j;
int coeff_prec, qlevel;
int coeffs[pred_order];
+ int32_t *decoded = s->decoded[channel];
// av_log(s->avctx, AV_LOG_DEBUG, " SUBFRAME LPC\n");
for (i = 0; i < pred_order; i++)
{
- s->decoded[channel][i] = get_sbits(&s->gb, s->curr_bps);
-// av_log(s->avctx, AV_LOG_DEBUG, " %d: %d\n", i, s->decoded[channel][i]);
+ decoded[i] = get_sbits(&s->gb, s->curr_bps);
+// av_log(s->avctx, AV_LOG_DEBUG, " %d: %d\n", i, decoded[i]);
}
coeff_prec = get_bits(&s->gb, 4) + 1;
if (decode_residuals(s, channel, pred_order) < 0)
return -1;
- for (i = pred_order; i < s->blocksize; i++)
- {
- sum = 0;
- for (j = 0; j < pred_order; j++)
- sum += coeffs[j] * s->decoded[channel][i-j-1];
- s->decoded[channel][i] += sum >> qlevel;
+ if (s->bps > 16) {
+ int64_t sum;
+ for (i = pred_order; i < s->blocksize; i++)
+ {
+ sum = 0;
+ for (j = 0; j < pred_order; j++)
+ sum += (int64_t)coeffs[j] * decoded[i-j-1];
+ decoded[i] += sum >> qlevel;
+ }
+ } else {
+ for (i = pred_order; i < s->blocksize-1; i += 2)
+ {
+ int c;
+ int d = decoded[i-pred_order];
+ int s0 = 0, s1 = 0;
+ for (j = pred_order-1; j > 0; j--)
+ {
+ c = coeffs[j];
+ s0 += c*d;
+ d = decoded[i-j];
+ s1 += c*d;
+ }
+ c = coeffs[0];
+ s0 += c*d;
+ d = decoded[i] += s0 >> qlevel;
+ s1 += c*d;
+ decoded[i+1] += s1 >> qlevel;
+ }
+ if (i < s->blocksize)
+ {
+ int sum = 0;
+ for (j = 0; j < pred_order; j++)
+ sum += coeffs[j] * decoded[i-j-1];
+ decoded[i] += sum >> qlevel;
+ }
}
return 0;
return 0;
}
-static int decode_frame(FLACContext *s)
+static int decode_frame(FLACContext *s, int alloc_data_size)
{
int blocksize_code, sample_rate_code, sample_size_code, assignment, i, crc8;
int decorrelation, bps, blocksize, samplerate;
return -1;
}
+ if(blocksize * s->channels * sizeof(int16_t) > alloc_data_size)
+ return -1;
+
if (sample_rate_code == 0){
samplerate= s->samplerate;
}else if ((sample_rate_code > 3) && (sample_rate_code < 12))
}
skip_bits(&s->gb, 8);
- crc8= av_crc(av_crc07, 0, s->gb.buffer, get_bits_count(&s->gb)/8);
+ crc8 = av_crc(av_crc_get_table(AV_CRC_8_ATM), 0,
+ s->gb.buffer, get_bits_count(&s->gb)/8);
if(crc8){
av_log(s->avctx, AV_LOG_ERROR, "header crc mismatch crc=%2X\n", crc8);
return -1;
static int flac_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
- uint8_t *buf, int buf_size)
+ const uint8_t *buf, int buf_size)
{
FLACContext *s = avctx->priv_data;
- int metadata_last, metadata_type, metadata_size;
int tmp = 0, i, j = 0, input_buf_size = 0;
int16_t *samples = data;
+ int alloc_data_size= *data_size;
+
+ *data_size=0;
if(s->max_framesize == 0){
s->max_framesize= 65536; // should hopefully be enough for the first header
init_get_bits(&s->gb, buf, buf_size*8);
- /* fLaC signature (be) */
- if (show_bits_long(&s->gb, 32) == bswap_32(ff_get_fourcc("fLaC")))
+ if (!metadata_parse(s))
{
- skip_bits(&s->gb, 32);
-
- av_log(s->avctx, AV_LOG_DEBUG, "STREAM HEADER\n");
- do {
- metadata_last = get_bits(&s->gb, 1);
- metadata_type = get_bits(&s->gb, 7);
- metadata_size = get_bits_long(&s->gb, 24);
-
- av_log(s->avctx, AV_LOG_DEBUG, " metadata block: flag = %d, type = %d, size = %d\n",
- metadata_last, metadata_type,
- metadata_size);
- if(metadata_size){
- switch(metadata_type)
- {
- case METADATA_TYPE_STREAMINFO:{
- metadata_streaminfo(s);
-
- /* Buffer might have been reallocated, reinit bitreader */
- if(buf != &s->bitstream[s->bitstream_index])
- {
- int bits_count = get_bits_count(&s->gb);
- buf= &s->bitstream[s->bitstream_index];
- init_get_bits(&s->gb, buf, buf_size*8);
- skip_bits(&s->gb, bits_count);
- }
-
- dump_headers(s);
- break;}
- default:
- for(i=0; i<metadata_size; i++)
- skip_bits(&s->gb, 8);
- }
- }
- } while(!metadata_last);
- }
- else
- {
-
tmp = show_bits(&s->gb, 16);
- if(tmp != 0xFFF8){
+ if((tmp & 0xFFFE) != 0xFFF8){
av_log(s->avctx, AV_LOG_ERROR, "FRAME HEADER not here\n");
- while(get_bits_count(&s->gb)/8+2 < buf_size && show_bits(&s->gb, 16) != 0xFFF8)
+ while(get_bits_count(&s->gb)/8+2 < buf_size && (show_bits(&s->gb, 16) & 0xFFFE) != 0xFFF8)
skip_bits(&s->gb, 8);
goto end; // we may not have enough bits left to decode a frame, so try next time
}
skip_bits(&s->gb, 16);
- if (decode_frame(s) < 0){
+ if (decode_frame(s, alloc_data_size) < 0){
av_log(s->avctx, AV_LOG_ERROR, "decode_frame() failed\n");
s->bitstream_size=0;
s->bitstream_index=0;
}
}
#else
+#define DECORRELATE(left, right)\
+ assert(s->channels == 2);\
+ for (i = 0; i < s->blocksize; i++)\
+ {\
+ int a= s->decoded[0][i];\
+ int b= s->decoded[1][i];\
+ *samples++ = ((left) << (24 - s->bps)) >> 8;\
+ *samples++ = ((right) << (24 - s->bps)) >> 8;\
+ }\
+ break;
+
switch(s->decorrelation)
{
case INDEPENDENT:
for (j = 0; j < s->blocksize; j++)
{
for (i = 0; i < s->channels; i++)
- *(samples++) = s->decoded[i][j];
+ *samples++ = (s->decoded[i][j] << (24 - s->bps)) >> 8;
}
break;
case LEFT_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- *(samples++) = s->decoded[0][i];
- *(samples++) = s->decoded[0][i] - s->decoded[1][i];
- }
- break;
+ DECORRELATE(a,a-b)
case RIGHT_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- *(samples++) = s->decoded[0][i] + s->decoded[1][i];
- *(samples++) = s->decoded[1][i];
- }
- break;
+ DECORRELATE(a+b,b)
case MID_SIDE:
- assert(s->channels == 2);
- for (i = 0; i < s->blocksize; i++)
- {
- int mid, side;
- mid = s->decoded[0][i];
- side = s->decoded[1][i];
-
-#if 1 //needs to be checked but IMHO it should be binary identical
- mid -= side>>1;
- *(samples++) = mid + side;
- *(samples++) = mid;
-#else
-
- mid <<= 1;
- if (side & 1)
- mid++;
- *(samples++) = (mid + side) >> 1;
- *(samples++) = (mid - side) >> 1;
-#endif
- }
- break;
+ DECORRELATE( (a-=b>>1) + b, a)
}
#endif
// s->last_blocksize = s->blocksize;
end:
- i= (get_bits_count(&s->gb)+7)/8;;
+ i= (get_bits_count(&s->gb)+7)/8;
if(i > buf_size){
av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
s->bitstream_size=0;
return i;
}
-static int flac_decode_close(AVCodecContext *avctx)
+static av_cold int flac_decode_close(AVCodecContext *avctx)
{
FLACContext *s = avctx->priv_data;
int i;
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