*/
/**
- * @file libavcodec/alsdec.c
+ * @file
* MPEG-4 ALS decoder
* @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
*/
#include "unary.h"
#include "mpeg4audio.h"
#include "bytestream.h"
+#include "bgmc.h"
#include <stdint.h>
};
+/** Tail codes used in arithmetic coding using block Gilbert-Moore codes.
+ */
+static const uint8_t tail_code[16][6] = {
+ { 74, 44, 25, 13, 7, 3},
+ { 68, 42, 24, 13, 7, 3},
+ { 58, 39, 23, 13, 7, 3},
+ {126, 70, 37, 19, 10, 5},
+ {132, 70, 37, 20, 10, 5},
+ {124, 70, 38, 20, 10, 5},
+ {120, 69, 37, 20, 11, 5},
+ {116, 67, 37, 20, 11, 5},
+ {108, 66, 36, 20, 10, 5},
+ {102, 62, 36, 20, 10, 5},
+ { 88, 58, 34, 19, 10, 5},
+ {162, 89, 49, 25, 13, 7},
+ {156, 87, 49, 26, 14, 7},
+ {150, 86, 47, 26, 14, 7},
+ {142, 84, 47, 26, 14, 7},
+ {131, 79, 46, 26, 14, 7}
+};
+
+
enum RA_Flag {
RA_FLAG_NONE,
RA_FLAG_FRAMES,
unsigned int frame_id; ///< the frame ID / number of the current frame
unsigned int js_switch; ///< if true, joint-stereo decoding is enforced
unsigned int num_blocks; ///< number of blocks used in the current frame
+ unsigned int s_max; ///< maximum Rice parameter allowed in entropy coding
+ uint8_t *bgmc_lut; ///< pointer at lookup tables used for BGMC
+ unsigned int *bgmc_lut_status; ///< pointer at lookup table status flags used for BGMC
int ltp_lag_length; ///< number of bits used for ltp lag value
int *use_ltp; ///< contains use_ltp flags for all channels
int *ltp_lag; ///< contains ltp lag values for all channels
}
MISSING_ERR(sconf->floating, "Floating point decoding", -1);
- MISSING_ERR(sconf->bgmc, "BGMC entropy decoding", -1);
MISSING_ERR(sconf->rlslms, "Adaptive RLS-LMS prediction", -1);
MISSING_ERR(sconf->chan_sort, "Channel sorting", 0);
unsigned int remaining = ctx->cur_frame_length;
for (b = 0; b < ctx->num_blocks; b++) {
- if (remaining < div_blocks[b]) {
+ if (remaining <= div_blocks[b]) {
div_blocks[b] = remaining;
ctx->num_blocks = b + 1;
break;
GetBitContext *gb = &ctx->gb;
unsigned int k;
unsigned int s[8];
+ unsigned int sx[8];
unsigned int sub_blocks, log2_sub_blocks, sb_length;
unsigned int start = 0;
unsigned int opt_order;
int sb;
int32_t *quant_cof = bd->quant_cof;
+ int32_t *current_res;
// ensure variable block decoding by reusing this field
sb_length = bd->block_length >> log2_sub_blocks;
-
if (sconf->bgmc) {
- // TODO: BGMC mode
+ s[0] = get_bits(gb, 8 + (sconf->resolution > 1));
+ for (k = 1; k < sub_blocks; k++)
+ s[k] = s[k - 1] + decode_rice(gb, 2);
+
+ for (k = 0; k < sub_blocks; k++) {
+ sx[k] = s[k] & 0x0F;
+ s [k] >>= 4;
+ }
} else {
s[0] = get_bits(gb, 4 + (sconf->resolution > 1));
for (k = 1; k < sub_blocks; k++)
*bd->use_ltp = get_bits1(gb);
if (*bd->use_ltp) {
+ int r, c;
+
bd->ltp_gain[0] = decode_rice(gb, 1) << 3;
bd->ltp_gain[1] = decode_rice(gb, 2) << 3;
- bd->ltp_gain[2] = ltp_gain_values[get_unary(gb, 0, 4)][get_bits(gb, 2)];
+ r = get_unary(gb, 0, 4);
+ c = get_bits(gb, 2);
+ bd->ltp_gain[2] = ltp_gain_values[r][c];
bd->ltp_gain[3] = decode_rice(gb, 2) << 3;
bd->ltp_gain[4] = decode_rice(gb, 1) << 3;
if (opt_order)
bd->raw_samples[0] = decode_rice(gb, avctx->bits_per_raw_sample - 4);
if (opt_order > 1)
- bd->raw_samples[1] = decode_rice(gb, s[0] + 3);
+ bd->raw_samples[1] = decode_rice(gb, FFMIN(s[0] + 3, ctx->s_max));
if (opt_order > 2)
- bd->raw_samples[2] = decode_rice(gb, s[0] + 1);
+ bd->raw_samples[2] = decode_rice(gb, FFMIN(s[0] + 1, ctx->s_max));
start = FFMIN(opt_order, 3);
}
// read all residuals
if (sconf->bgmc) {
- // TODO: BGMC mode
+ unsigned int delta[sub_blocks];
+ unsigned int k [sub_blocks];
+ unsigned int b = av_clip((av_ceil_log2(bd->block_length) - 3) >> 1, 0, 5);
+ unsigned int i = start;
+
+ // read most significant bits
+ unsigned int high;
+ unsigned int low;
+ unsigned int value;
+
+ ff_bgmc_decode_init(gb, &high, &low, &value);
+
+ current_res = bd->raw_samples + start;
+
+ for (sb = 0; sb < sub_blocks; sb++, i = 0) {
+ k [sb] = s[sb] > b ? s[sb] - b : 0;
+ delta[sb] = 5 - s[sb] + k[sb];
+
+ ff_bgmc_decode(gb, sb_length, current_res,
+ delta[sb], sx[sb], &high, &low, &value, ctx->bgmc_lut, ctx->bgmc_lut_status);
+
+ current_res += sb_length;
+ }
+
+ ff_bgmc_decode_end(gb);
+
+
+ // read least significant bits and tails
+ i = start;
+ current_res = bd->raw_samples + start;
+
+ for (sb = 0; sb < sub_blocks; sb++, i = 0) {
+ unsigned int cur_tail_code = tail_code[sx[sb]][delta[sb]];
+ unsigned int cur_k = k[sb];
+ unsigned int cur_s = s[sb];
+
+ for (; i < sb_length; i++) {
+ int32_t res = *current_res;
+
+ if (res == cur_tail_code) {
+ unsigned int max_msb = (2 + (sx[sb] > 2) + (sx[sb] > 10))
+ << (5 - delta[sb]);
+
+ res = decode_rice(gb, cur_s);
+
+ if (res >= 0) {
+ res += (max_msb ) << cur_k;
+ } else {
+ res -= (max_msb - 1) << cur_k;
+ }
+ } else {
+ if (res > cur_tail_code)
+ res--;
+
+ if (res & 1)
+ res = -res;
+
+ res >>= 1;
+
+ if (cur_k) {
+ res <<= cur_k;
+ res |= get_bits_long(gb, cur_k);
+ }
+ }
+
+ *current_res++ = res;
+ }
+ }
} else {
- int32_t *current_res = bd->raw_samples + start;
+ current_res = bd->raw_samples + start;
for (sb = 0; sb < sub_blocks; sb++, start = 0)
for (; start < sb_length; start++)
av_freep(&ctx->sconf.chan_pos);
+ ff_bgmc_end(&ctx->bgmc_lut, &ctx->bgmc_lut_status);
+
av_freep(&ctx->use_ltp);
av_freep(&ctx->ltp_lag);
av_freep(&ctx->ltp_gain);
return -1;
}
+ if (sconf->bgmc)
+ ff_bgmc_init(avctx, &ctx->bgmc_lut, &ctx->bgmc_lut_status);
+
if (sconf->floating) {
avctx->sample_fmt = SAMPLE_FMT_FLT;
avctx->bits_per_raw_sample = 32;
avctx->bits_per_raw_sample = (sconf->resolution + 1) * 8;
}
+ // set maximum Rice parameter for progressive decoding based on resolution
+ // This is not specified in 14496-3 but actually done by the reference
+ // codec RM22 revision 2.
+ ctx->s_max = sconf->resolution > 1 ? 31 : 15;
+
// set lag value for long-term prediction
ctx->ltp_lag_length = 8 + (avctx->sample_rate >= 96000) +
(avctx->sample_rate >= 192000);
// allocate and assign channel data buffer for mcc mode
if (sconf->mc_coding) {
ctx->chan_data_buffer = av_malloc(sizeof(*ctx->chan_data_buffer) *
- num_buffers);
- ctx->chan_data = av_malloc(sizeof(ALSChannelData) *
+ num_buffers * num_buffers);
+ ctx->chan_data = av_malloc(sizeof(*ctx->chan_data) *
num_buffers);
ctx->reverted_channels = av_malloc(sizeof(*ctx->reverted_channels) *
num_buffers);
}
for (c = 0; c < num_buffers; c++)
- ctx->chan_data[c] = ctx->chan_data_buffer + c;
+ ctx->chan_data[c] = ctx->chan_data_buffer + c * num_buffers;
} else {
ctx->chan_data = NULL;
ctx->chan_data_buffer = NULL;
AVCodec als_decoder = {
"als",
- CODEC_TYPE_AUDIO,
+ AVMEDIA_TYPE_AUDIO,
CODEC_ID_MP4ALS,
sizeof(ALSDecContext),
decode_init,
projects / ffmpeg / blobdiff