* Shorten decoder
* Copyright (c) 2005 Jeff Muizelaar
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
*
*/
-#define DEBUG
#include <limits.h>
#include "avcodec.h"
+#include "bytestream.h"
#include "get_bits.h"
#include "golomb.h"
#define FN_ZERO 8
#define FN_VERBATIM 9
+/** indicates if the FN_* command is audio or non-audio */
+static const uint8_t is_audio_command[10] = { 1, 1, 1, 1, 0, 0, 0, 1, 1, 0 };
+
#define VERBATIM_CKSIZE_SIZE 5
#define VERBATIM_BYTE_SIZE 8
#define CANONICAL_HEADER_SIZE 44
typedef struct ShortenContext {
AVCodecContext *avctx;
+ AVFrame frame;
GetBitContext gb;
int min_framesize, max_framesize;
int blocksize;
int bitindex;
int32_t lpcqoffset;
+ int got_header;
+ int got_quit_command;
} ShortenContext;
static av_cold int shorten_decode_init(AVCodecContext * avctx)
s->avctx = avctx;
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+ avcodec_get_frame_defaults(&s->frame);
+ avctx->coded_frame = &s->frame;
+
return 0;
}
{
int i, chan;
int *coeffs;
+ void *tmp_ptr;
for (chan=0; chan<s->channels; chan++) {
if(FFMAX(1, s->nmean) >= UINT_MAX/sizeof(int32_t)){
return -1;
}
- s->offset[chan] = av_realloc(s->offset[chan], sizeof(int32_t)*FFMAX(1, s->nmean));
+ tmp_ptr = av_realloc(s->offset[chan], sizeof(int32_t)*FFMAX(1, s->nmean));
+ if (!tmp_ptr)
+ return AVERROR(ENOMEM);
+ s->offset[chan] = tmp_ptr;
- s->decoded[chan] = av_realloc(s->decoded[chan], sizeof(int32_t)*(s->blocksize + s->nwrap));
+ tmp_ptr = av_realloc(s->decoded[chan], sizeof(int32_t)*(s->blocksize + s->nwrap));
+ if (!tmp_ptr)
+ return AVERROR(ENOMEM);
+ s->decoded[chan] = tmp_ptr;
for (i=0; i<s->nwrap; i++)
s->decoded[chan][i] = 0;
s->decoded[chan] += s->nwrap;
if (s->bitshift != 0)
for (i = 0; i < s->blocksize; i++)
- buffer[s->nwrap + i] <<= s->bitshift;
+ buffer[i] <<= s->bitshift;
}
-static void init_offset(ShortenContext *s)
+static int init_offset(ShortenContext *s)
{
int32_t mean = 0;
int chan, i;
break;
default:
av_log(s->avctx, AV_LOG_ERROR, "unknown audio type");
- abort();
+ return AVERROR_INVALIDDATA;
}
for (chan = 0; chan < s->channels; chan++)
for (i = 0; i < nblock; i++)
s->offset[chan][i] = mean;
+ return 0;
}
-static inline int get_le32(GetBitContext *gb)
-{
- 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)
+static int decode_wave_header(AVCodecContext *avctx, const uint8_t *header,
+ int header_size)
{
- GetBitContext hb;
int len;
- int chunk_size;
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");
return -1;
}
- chunk_size = get_le32(&hb);
+ 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");
return -1;
}
- while (get_le32(&hb) != MKTAG('f','m','t',' ')) {
- len = get_le32(&hb);
- skip_bits(&hb, 8*len);
+ while (bytestream_get_le32(&header) != MKTAG('f','m','t',' ')) {
+ len = bytestream_get_le32(&header);
+ header += len;
}
- len = get_le32(&hb);
+ len = bytestream_get_le32(&header);
if (len < 16) {
av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");
return -1;
}
- wave_format = get_le16(&hb);
+ wave_format = bytestream_get_le16(&header);
switch (wave_format) {
case WAVE_FORMAT_PCM:
return -1;
}
- avctx->channels = get_le16(&hb);
- avctx->sample_rate = get_le32(&hb);
- avctx->bit_rate = get_le32(&hb) * 8;
- avctx->block_align = get_le16(&hb);
- avctx->bits_per_coded_sample = get_le16(&hb);
+ header += 2; // skip channels (already got from shorten header)
+ avctx->sample_rate = bytestream_get_le32(&header);
+ header += 4; // skip bit rate (represents original uncompressed bit rate)
+ header += 2; // skip block align (not needed)
+ avctx->bits_per_coded_sample = bytestream_get_le16(&header);
if (avctx->bits_per_coded_sample != 16) {
av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n");
return 0;
}
-static int16_t * interleave_buffer(int16_t *samples, int nchan, int blocksize, int32_t **buffer) {
+static void interleave_buffer(int16_t *samples, int nchan, int blocksize,
+ int32_t **buffer)
+{
int i, chan;
for (i=0; i<blocksize; i++)
for (chan=0; chan < nchan; chan++)
- *samples++ = FFMIN(buffer[chan][i], 32768);
- return samples;
+ *samples++ = av_clip_int16(buffer[chan][i]);
}
-static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_size, int pred_order)
+static const int fixed_coeffs[3][3] = {
+ { 1, 0, 0 },
+ { 2, -1, 0 },
+ { 3, -3, 1 }
+};
+
+static int decode_subframe_lpc(ShortenContext *s, int command, int channel,
+ int residual_size, int32_t coffset)
{
- int sum, i, j;
- int *coeffs = s->coeffs;
+ int pred_order, sum, qshift, init_sum, i, j;
+ const int *coeffs;
+
+ if (command == FN_QLPC) {
+ /* read/validate prediction order */
+ pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);
+ if (pred_order > s->nwrap) {
+ av_log(s->avctx, AV_LOG_ERROR, "invalid pred_order %d\n", pred_order);
+ return AVERROR(EINVAL);
+ }
+ /* read LPC coefficients */
+ for (i=0; i<pred_order; i++)
+ s->coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);
+ coeffs = s->coeffs;
+
+ qshift = LPCQUANT;
+ } else {
+ /* fixed LPC coeffs */
+ pred_order = command;
+ coeffs = fixed_coeffs[pred_order-1];
+ qshift = 0;
+ }
- for (i=0; i<pred_order; i++)
- coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);
+ /* subtract offset from previous samples to use in prediction */
+ if (command == FN_QLPC && coffset)
+ for (i = -pred_order; i < 0; i++)
+ s->decoded[channel][i] -= coffset;
+ /* decode residual and do LPC prediction */
+ init_sum = pred_order ? (command == FN_QLPC ? s->lpcqoffset : 0) : coffset;
for (i=0; i < s->blocksize; i++) {
- sum = s->lpcqoffset;
+ sum = init_sum;
for (j=0; j<pred_order; j++)
sum += coeffs[j] * s->decoded[channel][i-j-1];
- s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> LPCQUANT);
+ s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> qshift);
}
+
+ /* add offset to current samples */
+ if (command == FN_QLPC && coffset)
+ for (i = 0; i < s->blocksize; i++)
+ s->decoded[channel][i] += coffset;
+
+ return 0;
}
+static int read_header(ShortenContext *s)
+{
+ int i, ret;
+ int maxnlpc = 0;
+ /* shorten signature */
+ if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
+ av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
+ return -1;
+ }
+
+ s->lpcqoffset = 0;
+ s->blocksize = DEFAULT_BLOCK_SIZE;
+ s->nmean = -1;
+ s->version = get_bits(&s->gb, 8);
+ s->internal_ftype = get_uint(s, TYPESIZE);
+
+ s->channels = get_uint(s, CHANSIZE);
+ if (s->channels > MAX_CHANNELS) {
+ av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
+ return -1;
+ }
+ s->avctx->channels = s->channels;
+
+ /* get blocksize if version > 0 */
+ if (s->version > 0) {
+ int skip_bytes, blocksize;
+
+ blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
+ if (!blocksize || blocksize > MAX_BLOCKSIZE) {
+ av_log(s->avctx, AV_LOG_ERROR, "invalid or unsupported block size: %d\n",
+ blocksize);
+ return AVERROR(EINVAL);
+ }
+ s->blocksize = blocksize;
+
+ maxnlpc = get_uint(s, LPCQSIZE);
+ s->nmean = get_uint(s, 0);
+
+ skip_bytes = get_uint(s, NSKIPSIZE);
+ for (i=0; i<skip_bytes; i++) {
+ skip_bits(&s->gb, 8);
+ }
+ }
+ s->nwrap = FFMAX(NWRAP, maxnlpc);
+
+ if ((ret = allocate_buffers(s)) < 0)
+ return ret;
+
+ if ((ret = init_offset(s)) < 0)
+ return ret;
+
+ if (s->version > 1)
+ s->lpcqoffset = V2LPCQOFFSET;
+
+ if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
+ av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
+ return -1;
+ }
+
+ s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
+ if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
+ av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
+ return -1;
+ }
-static int shorten_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+ for (i=0; i<s->header_size; i++)
+ s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
+
+ if (decode_wave_header(s->avctx, s->header, s->header_size) < 0)
+ return -1;
+
+ s->cur_chan = 0;
+ s->bitshift = 0;
+
+ s->got_header = 1;
+
+ return 0;
+}
+
+static int shorten_decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
ShortenContext *s = avctx->priv_data;
int i, input_buf_size = 0;
- int16_t *samples = data;
+ int ret;
+
+ /* allocate internal bitstream buffer */
if(s->max_framesize == 0){
+ void *tmp_ptr;
s->max_framesize= 1024; // should hopefully be enough for the first header
- s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
+ tmp_ptr = av_fast_realloc(s->bitstream, &s->allocated_bitstream_size,
+ s->max_framesize);
+ if (!tmp_ptr) {
+ av_log(avctx, AV_LOG_ERROR, "error allocating bitstream buffer\n");
+ return AVERROR(ENOMEM);
+ }
+ s->bitstream = tmp_ptr;
}
+ /* append current packet data to bitstream buffer */
if(1 && s->max_framesize){//FIXME truncated
buf_size= FFMIN(buf_size, s->max_framesize - s->bitstream_size);
input_buf_size= buf_size;
if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
- // printf("memmove\n");
memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
s->bitstream_index=0;
}
- memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
+ if (buf)
+ memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
buf= &s->bitstream[s->bitstream_index];
buf_size += s->bitstream_size;
s->bitstream_size= buf_size;
- if(buf_size < s->max_framesize){
- //av_dlog(avctx, "wanna more data ... %d\n", buf_size);
- *data_size = 0;
+ /* do not decode until buffer has at least max_framesize bytes or
+ the end of the file has been reached */
+ if (buf_size < s->max_framesize && avpkt->data) {
+ *got_frame_ptr = 0;
return input_buf_size;
}
}
+ /* init and position bitstream reader */
init_get_bits(&s->gb, buf, buf_size*8);
skip_bits(&s->gb, s->bitindex);
- if (!s->blocksize)
- {
- int maxnlpc = 0;
- /* shorten signature */
- if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
- av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
- return -1;
- }
- s->lpcqoffset = 0;
- s->blocksize = DEFAULT_BLOCK_SIZE;
- s->channels = 1;
- s->nmean = -1;
- s->version = get_bits(&s->gb, 8);
- s->internal_ftype = get_uint(s, TYPESIZE);
+ /* process header or next subblock */
+ if (!s->got_header) {
+ if ((ret = read_header(s)) < 0)
+ return ret;
+ *got_frame_ptr = 0;
+ goto finish_frame;
+ }
- s->channels = get_uint(s, CHANSIZE);
- if (s->channels > MAX_CHANNELS) {
- av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
- return -1;
- }
+ /* if quit command was read previously, don't decode anything */
+ if (s->got_quit_command) {
+ *got_frame_ptr = 0;
+ return avpkt->size;
+ }
- /* get blocksize if version > 0 */
- if (s->version > 0) {
- int skip_bytes;
- s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
- maxnlpc = get_uint(s, LPCQSIZE);
- s->nmean = get_uint(s, 0);
+ s->cur_chan = 0;
+ while (s->cur_chan < s->channels) {
+ int cmd;
+ int len;
- skip_bytes = get_uint(s, NSKIPSIZE);
- for (i=0; i<skip_bytes; i++) {
- skip_bits(&s->gb, 8);
- }
+ if (get_bits_left(&s->gb) < 3+FNSIZE) {
+ *got_frame_ptr = 0;
+ break;
}
- s->nwrap = FFMAX(NWRAP, maxnlpc);
- if (allocate_buffers(s))
- return -1;
-
- init_offset(s);
-
- if (s->version > 1)
- s->lpcqoffset = V2LPCQOFFSET;
-
- if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
- av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
- return -1;
- }
+ cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);
- s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
- if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
- av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
- return -1;
+ if (cmd > FN_VERBATIM) {
+ av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);
+ *got_frame_ptr = 0;
+ break;
}
- for (i=0; i<s->header_size; i++)
- s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
-
- if (decode_wave_header(avctx, s->header, s->header_size) < 0)
- return -1;
-
- s->cur_chan = 0;
- s->bitshift = 0;
- }
- else
- {
- int cmd;
- int len;
- cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);
- switch (cmd) {
- case FN_ZERO:
- case FN_DIFF0:
- case FN_DIFF1:
- case FN_DIFF2:
- case FN_DIFF3:
- case FN_QLPC:
- {
- int residual_size = 0;
- int channel = s->cur_chan;
- int32_t coffset;
- if (cmd != FN_ZERO) {
- residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);
- /* this is a hack as version 0 differed in defintion of get_sr_golomb_shorten */
- if (s->version == 0)
- residual_size--;
- }
-
- if (s->nmean == 0)
- coffset = s->offset[channel][0];
- else {
- int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;
- for (i=0; i<s->nmean; i++)
- sum += s->offset[channel][i];
- coffset = sum / s->nmean;
- if (s->version >= 2)
- coffset >>= FFMIN(1, s->bitshift);
- }
- switch (cmd) {
- case FN_ZERO:
- for (i=0; i<s->blocksize; i++)
- s->decoded[channel][i] = 0;
- break;
- case FN_DIFF0:
- for (i=0; i<s->blocksize; i++)
- s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + coffset;
- break;
- case FN_DIFF1:
- for (i=0; i<s->blocksize; i++)
- s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + s->decoded[channel][i - 1];
- break;
- case FN_DIFF2:
- for (i=0; i<s->blocksize; i++)
- s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 2*s->decoded[channel][i-1]
- - s->decoded[channel][i-2];
- break;
- case FN_DIFF3:
- for (i=0; i<s->blocksize; i++)
- s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 3*s->decoded[channel][i-1]
- - 3*s->decoded[channel][i-2]
- + s->decoded[channel][i-3];
- break;
- case FN_QLPC:
- {
- int pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);
- if (pred_order > s->nwrap) {
- av_log(avctx, AV_LOG_ERROR,
- "invalid pred_order %d\n",
- pred_order);
- return -1;
- }
- for (i=0; i<pred_order; i++)
- s->decoded[channel][i - pred_order] -= coffset;
- decode_subframe_lpc(s, channel, residual_size, pred_order);
- if (coffset != 0)
- for (i=0; i < s->blocksize; i++)
- s->decoded[channel][i] += coffset;
- }
+ if (!is_audio_command[cmd]) {
+ /* process non-audio command */
+ switch (cmd) {
+ case FN_VERBATIM:
+ len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
+ while (len--) {
+ get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
}
- if (s->nmean > 0) {
- int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;
- for (i=0; i<s->blocksize; i++)
- sum += s->decoded[channel][i];
-
- for (i=1; i<s->nmean; i++)
- s->offset[channel][i-1] = s->offset[channel][i];
-
- if (s->version < 2)
- s->offset[channel][s->nmean - 1] = sum / s->blocksize;
- else
- s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;
+ break;
+ case FN_BITSHIFT:
+ s->bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);
+ break;
+ case FN_BLOCKSIZE: {
+ int blocksize = get_uint(s, av_log2(s->blocksize));
+ if (blocksize > s->blocksize) {
+ av_log(avctx, AV_LOG_ERROR, "Increasing block size is not supported\n");
+ return AVERROR_PATCHWELCOME;
}
- for (i=-s->nwrap; i<0; i++)
- s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];
-
- fix_bitshift(s, s->decoded[channel]);
-
- s->cur_chan++;
- if (s->cur_chan == s->channels) {
- samples = interleave_buffer(samples, s->channels, s->blocksize, s->decoded);
- s->cur_chan = 0;
- goto frame_done;
+ if (!blocksize || blocksize > MAX_BLOCKSIZE) {
+ av_log(avctx, AV_LOG_ERROR, "invalid or unsupported "
+ "block size: %d\n", blocksize);
+ return AVERROR(EINVAL);
}
+ s->blocksize = blocksize;
break;
}
+ case FN_QUIT:
+ s->got_quit_command = 1;
+ break;
+ }
+ if (cmd == FN_BLOCKSIZE || cmd == FN_QUIT) {
+ *got_frame_ptr = 0;
break;
- case FN_VERBATIM:
- len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
- while (len--) {
- get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
+ }
+ } else {
+ /* process audio command */
+ int residual_size = 0;
+ int channel = s->cur_chan;
+ int32_t coffset;
+
+ /* get Rice code for residual decoding */
+ if (cmd != FN_ZERO) {
+ residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);
+ /* this is a hack as version 0 differed in defintion of get_sr_golomb_shorten */
+ if (s->version == 0)
+ residual_size--;
+ }
+
+ /* calculate sample offset using means from previous blocks */
+ if (s->nmean == 0)
+ coffset = s->offset[channel][0];
+ else {
+ int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;
+ for (i=0; i<s->nmean; i++)
+ sum += s->offset[channel][i];
+ coffset = sum / s->nmean;
+ if (s->version >= 2)
+ coffset >>= FFMIN(1, s->bitshift);
+ }
+
+ /* decode samples for this channel */
+ if (cmd == FN_ZERO) {
+ for (i=0; i<s->blocksize; i++)
+ s->decoded[channel][i] = 0;
+ } else {
+ if ((ret = decode_subframe_lpc(s, cmd, channel, residual_size, coffset)) < 0)
+ return ret;
+ }
+
+ /* update means with info from the current block */
+ if (s->nmean > 0) {
+ int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;
+ for (i=0; i<s->blocksize; i++)
+ sum += s->decoded[channel][i];
+
+ for (i=1; i<s->nmean; i++)
+ s->offset[channel][i-1] = s->offset[channel][i];
+
+ if (s->version < 2)
+ s->offset[channel][s->nmean - 1] = sum / s->blocksize;
+ else
+ s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;
+ }
+
+ /* copy wrap samples for use with next block */
+ for (i=-s->nwrap; i<0; i++)
+ s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];
+
+ /* shift samples to add in unused zero bits which were removed
+ during encoding */
+ fix_bitshift(s, s->decoded[channel]);
+
+ /* if this is the last channel in the block, output the samples */
+ s->cur_chan++;
+ if (s->cur_chan == s->channels) {
+ /* get output buffer */
+ s->frame.nb_samples = s->blocksize;
+ if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
}
- break;
- case FN_BITSHIFT:
- s->bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);
- break;
- case FN_BLOCKSIZE:
- s->blocksize = get_uint(s, av_log2(s->blocksize));
- break;
- case FN_QUIT:
- *data_size = 0;
- return buf_size;
- break;
- default:
- av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);
- return -1;
- break;
+ /* interleave output */
+ interleave_buffer((int16_t *)s->frame.data[0], s->channels,
+ s->blocksize, s->decoded);
+
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = s->frame;
+ }
}
}
-frame_done:
- *data_size = (int8_t *)samples - (int8_t *)data;
+ if (s->cur_chan < s->channels)
+ *got_frame_ptr = 0;
- // s->last_blocksize = s->blocksize;
+finish_frame:
s->bitindex = get_bits_count(&s->gb) - 8*((get_bits_count(&s->gb))/8);
i= (get_bits_count(&s->gb))/8;
if (i > buf_size) {
}
av_freep(&s->bitstream);
av_freep(&s->coeffs);
- return 0;
-}
-static void shorten_flush(AVCodecContext *avctx){
- ShortenContext *s = avctx->priv_data;
-
- s->bitstream_size=
- s->bitstream_index= 0;
+ return 0;
}
AVCodec ff_shorten_decoder = {
- "shorten",
- AVMEDIA_TYPE_AUDIO,
- CODEC_ID_SHORTEN,
- sizeof(ShortenContext),
- shorten_decode_init,
- NULL,
- shorten_decode_close,
- shorten_decode_frame,
- .flush= shorten_flush,
+ .name = "shorten",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = CODEC_ID_SHORTEN,
+ .priv_data_size = sizeof(ShortenContext),
+ .init = shorten_decode_init,
+ .close = shorten_decode_close,
+ .decode = shorten_decode_frame,
+ .capabilities = CODEC_CAP_DELAY | CODEC_CAP_DR1,
.long_name= NULL_IF_CONFIG_SMALL("Shorten"),
};