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-rw-r--r--libavcodec/ac3dec_data.c6
-rw-r--r--libavcodec/ac3dec_data.h1
-rw-r--r--libavcodec/ac3enc.c147
-rw-r--r--libavcodec/ac3enc_fixed.h1
-rw-r--r--libavcodec/ac3enc_float.h1
-rw-r--r--libavcodec/ac3tab.c6
-rw-r--r--libavcodec/ac3tab.h1
-rw-r--r--tests/ref/acodec/ac3_fixed2
-rw-r--r--tests/ref/seek/ac3_rm21
9 files changed, 152 insertions, 34 deletions
diff --git a/libavcodec/ac3dec_data.c b/libavcodec/ac3dec_data.c
index ea13d3de51..c40390245c 100644
--- a/libavcodec/ac3dec_data.c
+++ b/libavcodec/ac3dec_data.c
@@ -43,12 +43,6 @@ const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3] = {
{ 3, 0, 1 }, { 3, 0, 2 }, { 3, 1, 0 }, { 3, 1, 1 }
};
-/**
- * Table of bin locations for rematrixing bands
- * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
- */
-const uint8_t ff_ac3_rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };
-
const uint8_t ff_eac3_hebap_tab[64] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 8,
8, 8, 9, 9, 9, 10, 10, 10, 10, 11,
diff --git a/libavcodec/ac3dec_data.h b/libavcodec/ac3dec_data.h
index 9ed7c73188..e2ab7ddbe5 100644
--- a/libavcodec/ac3dec_data.h
+++ b/libavcodec/ac3dec_data.h
@@ -25,7 +25,6 @@
#include <stdint.h>
extern const uint8_t ff_ac3_ungroup_3_in_5_bits_tab[32][3];
-extern const uint8_t ff_ac3_rematrix_band_tab[5];
extern const uint8_t ff_eac3_hebap_tab[64];
extern const uint8_t ff_eac3_default_cpl_band_struct[18];
diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c
index d9a54325c0..f96883464f 100644
--- a/libavcodec/ac3enc.c
+++ b/libavcodec/ac3enc.c
@@ -45,6 +45,12 @@
/** Maximum number of exponent groups. +1 for separate DC exponent. */
#define AC3_MAX_EXP_GROUPS 85
+/* stereo rematrixing algorithms */
+#define AC3_REMATRIXING_IS_STATIC 0x1
+#define AC3_REMATRIXING_SUMS 0
+#define AC3_REMATRIXING_NONE 1
+#define AC3_REMATRIXING_ALWAYS 3
+
/** Scale a float value by 2^bits and convert to an integer. */
#define SCALE_FLOAT(a, bits) lrintf((a) * (float)(1 << (bits)))
@@ -71,6 +77,8 @@ typedef struct AC3Block {
uint16_t **qmant; ///< quantized mantissas
uint8_t exp_strategy[AC3_MAX_CHANNELS]; ///< exponent strategies
int8_t exp_shift[AC3_MAX_CHANNELS]; ///< exponent shift values
+ uint8_t new_rematrixing_strategy; ///< send new rematrixing flags in this block
+ uint8_t rematrixing_flags[4]; ///< rematrixing flags
} AC3Block;
/**
@@ -107,6 +115,8 @@ typedef struct AC3EncodeContext {
int bandwidth_code[AC3_MAX_CHANNELS]; ///< bandwidth code (0 to 60) (chbwcod)
int nb_coefs[AC3_MAX_CHANNELS];
+ int rematrixing; ///< determines how rematrixing strategy is calculated
+
/* bitrate allocation control */
int slow_gain_code; ///< slow gain code (sgaincod)
int slow_decay_code; ///< slow decay code (sdcycod)
@@ -262,6 +272,114 @@ static void apply_mdct(AC3EncodeContext *s)
/**
+ * Initialize stereo rematrixing.
+ * If the strategy does not change for each frame, set the rematrixing flags.
+ */
+static void rematrixing_init(AC3EncodeContext *s)
+{
+ if (s->channel_mode == AC3_CHMODE_STEREO)
+ s->rematrixing = AC3_REMATRIXING_SUMS;
+ else
+ s->rematrixing = AC3_REMATRIXING_NONE;
+ /* NOTE: AC3_REMATRIXING_ALWAYS might be used in
+ the future in conjunction with channel coupling. */
+
+ if (s->rematrixing & AC3_REMATRIXING_IS_STATIC) {
+ int flag = (s->rematrixing == AC3_REMATRIXING_ALWAYS);
+ s->blocks[0].new_rematrixing_strategy = 1;
+ memset(s->blocks[0].rematrixing_flags, flag,
+ sizeof(s->blocks[0].rematrixing_flags));
+ }
+}
+
+
+/**
+ * Determine rematrixing flags for each block and band.
+ */
+static void compute_rematrixing_strategy(AC3EncodeContext *s)
+{
+ int nb_coefs;
+ int blk, bnd, i;
+ AC3Block *block, *block0;
+
+ if (s->rematrixing & AC3_REMATRIXING_IS_STATIC)
+ return;
+
+ nb_coefs = FFMIN(s->nb_coefs[0], s->nb_coefs[1]);
+
+ s->blocks[0].new_rematrixing_strategy = 1;
+ for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ block = &s->blocks[blk];
+ for (bnd = 0; bnd < 4; bnd++) {
+ /* calculate calculate sum of squared coeffs for one band in one block */
+ int start = ff_ac3_rematrix_band_tab[bnd];
+ int end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
+ CoefSumType sum[4] = {0,};
+ for (i = start; i < end; i++) {
+ CoefType lt = block->mdct_coef[0][i];
+ CoefType rt = block->mdct_coef[1][i];
+ CoefType md = lt + rt;
+ CoefType sd = lt - rt;
+ sum[0] += lt * lt;
+ sum[1] += rt * rt;
+ sum[2] += md * md;
+ sum[3] += sd * sd;
+ }
+
+ /* compare sums to determine if rematrixing will be used for this band */
+ if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
+ block->rematrixing_flags[bnd] = 1;
+ else
+ block->rematrixing_flags[bnd] = 0;
+
+ /* determine if new rematrixing flags will be sent */
+ if (blk &&
+ !block->new_rematrixing_strategy &&
+ block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
+ block->new_rematrixing_strategy = 1;
+ }
+ }
+ block0 = block;
+ }
+}
+
+
+/**
+ * Apply stereo rematrixing to coefficients based on rematrixing flags.
+ */
+static void apply_rematrixing(AC3EncodeContext *s)
+{
+ int nb_coefs;
+ int blk, bnd, i;
+ int start, end;
+ uint8_t *flags;
+
+ if (s->rematrixing == AC3_REMATRIXING_NONE)
+ return;
+
+ nb_coefs = FFMIN(s->nb_coefs[0], s->nb_coefs[1]);
+
+ for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
+ AC3Block *block = &s->blocks[blk];
+ if (block->new_rematrixing_strategy)
+ flags = block->rematrixing_flags;
+ for (bnd = 0; bnd < 4; bnd++) {
+ if (flags[bnd]) {
+ start = ff_ac3_rematrix_band_tab[bnd];
+ end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
+ for (i = start; i < end; i++) {
+ int32_t lt = block->fixed_coef[0][i];
+ int32_t rt = block->fixed_coef[1][i];
+ block->fixed_coef[0][i] = (lt + rt) >> 1;
+ block->fixed_coef[1][i] = (lt - rt) >> 1;
+ }
+ }
+ }
+ }
+}
+
+
+/**
* Initialize exponent tables.
*/
static av_cold void exponent_init(AC3EncodeContext *s)
@@ -592,7 +710,6 @@ static void count_frame_bits_fixed(AC3EncodeContext *s)
/* assumptions:
* no dynamic range codes
* no channel coupling
- * no rematrixing
* bit allocation parameters do not change between blocks
* SNR offsets do not change between blocks
* no delta bit allocation
@@ -609,8 +726,6 @@ static void count_frame_bits_fixed(AC3EncodeContext *s)
frame_bits += s->fbw_channels * 2 + 2; /* blksw * c, dithflag * c, dynrnge, cplstre */
if (s->channel_mode == AC3_CHMODE_STEREO) {
frame_bits++; /* rematstr */
- if (!blk)
- frame_bits += 4;
}
frame_bits += 2 * s->fbw_channels; /* chexpstr[2] * c */
if (s->lfe_on)
@@ -681,6 +796,13 @@ static void count_frame_bits(AC3EncodeContext *s)
for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
uint8_t *exp_strategy = s->blocks[blk].exp_strategy;
+
+ /* stereo rematrixing */
+ if (s->channel_mode == AC3_CHMODE_STEREO &&
+ s->blocks[blk].new_rematrixing_strategy) {
+ frame_bits += 4;
+ }
+
for (ch = 0; ch < s->fbw_channels; ch++) {
if (exp_strategy[ch] != EXP_REUSE)
frame_bits += 6 + 2; /* chbwcod[6], gainrng[2] */
@@ -1194,16 +1316,11 @@ static void output_audio_block(AC3EncodeContext *s, int block_num)
/* stereo rematrixing */
if (s->channel_mode == AC3_CHMODE_STEREO) {
- if (!block_num) {
- /* first block must define rematrixing (rematstr) */
- put_bits(&s->pb, 1, 1);
-
- /* dummy rematrixing rematflg(1:4)=0 */
+ put_bits(&s->pb, 1, block->new_rematrixing_strategy);
+ if (block->new_rematrixing_strategy) {
+ /* rematrixing flags */
for (rbnd = 0; rbnd < 4; rbnd++)
- put_bits(&s->pb, 1, 0);
- } else {
- /* no matrixing (but should be used in the future) */
- put_bits(&s->pb, 1, 0);
+ put_bits(&s->pb, 1, block->rematrixing_flags[rbnd]);
}
}
@@ -1394,8 +1511,12 @@ static int ac3_encode_frame(AVCodecContext *avctx, unsigned char *frame,
apply_mdct(s);
+ compute_rematrixing_strategy(s);
+
scale_coefficients(s);
+ apply_rematrixing(s);
+
process_exponents(s);
ret = compute_bit_allocation(s);
@@ -1707,6 +1828,8 @@ static av_cold int ac3_encode_init(AVCodecContext *avctx)
set_bandwidth(s);
+ rematrixing_init(s);
+
exponent_init(s);
bit_alloc_init(s);
diff --git a/libavcodec/ac3enc_fixed.h b/libavcodec/ac3enc_fixed.h
index 32d29a9bae..12c8ace4aa 100644
--- a/libavcodec/ac3enc_fixed.h
+++ b/libavcodec/ac3enc_fixed.h
@@ -34,6 +34,7 @@
typedef int16_t SampleType;
typedef int32_t CoefType;
+typedef int64_t CoefSumType;
/**
diff --git a/libavcodec/ac3enc_float.h b/libavcodec/ac3enc_float.h
index 29a479a00e..1726ca045f 100644
--- a/libavcodec/ac3enc_float.h
+++ b/libavcodec/ac3enc_float.h
@@ -34,6 +34,7 @@
typedef float SampleType;
typedef float CoefType;
+typedef float CoefSumType;
typedef struct AC3MDCTContext {
diff --git a/libavcodec/ac3tab.c b/libavcodec/ac3tab.c
index 79f628fbd9..4fc0824a46 100644
--- a/libavcodec/ac3tab.c
+++ b/libavcodec/ac3tab.c
@@ -132,6 +132,12 @@ const uint16_t ff_ac3_bitrate_tab[19] = {
160, 192, 224, 256, 320, 384, 448, 512, 576, 640
};
+/**
+ * Table of bin locations for rematrixing bands
+ * reference: Section 7.5.2 Rematrixing : Frequency Band Definitions
+ */
+const uint8_t ff_ac3_rematrix_band_tab[5] = { 13, 25, 37, 61, 253 };
+
/* AC-3 MDCT window */
/* MDCT window */
diff --git a/libavcodec/ac3tab.h b/libavcodec/ac3tab.h
index 4d41337d3a..dd8cabfcfd 100644
--- a/libavcodec/ac3tab.h
+++ b/libavcodec/ac3tab.h
@@ -32,6 +32,7 @@ extern const uint8_t ff_ac3_enc_channel_map[8][2][6];
extern const uint8_t ff_ac3_dec_channel_map[8][2][6];
extern const uint16_t ff_ac3_sample_rate_tab[3];
extern const uint16_t ff_ac3_bitrate_tab[19];
+extern const uint8_t ff_ac3_rematrix_band_tab[5];
extern const int16_t ff_ac3_window[AC3_WINDOW_SIZE/2];
extern const uint8_t ff_ac3_log_add_tab[260];
extern const uint16_t ff_ac3_hearing_threshold_tab[AC3_CRITICAL_BANDS][3];
diff --git a/tests/ref/acodec/ac3_fixed b/tests/ref/acodec/ac3_fixed
index 3ca8219e63..17159e18a7 100644
--- a/tests/ref/acodec/ac3_fixed
+++ b/tests/ref/acodec/ac3_fixed
@@ -1,2 +1,2 @@
-b315176b519a63a35cb91566e768f62b *./tests/data/acodec/ac3.rm
+9823c8f74097eab5d148cf0536ae932e *./tests/data/acodec/ac3.rm
98751 ./tests/data/acodec/ac3.rm
diff --git a/tests/ref/seek/ac3_rm b/tests/ref/seek/ac3_rm
index 6d47c47281..7b7d5b0bf7 100644
--- a/tests/ref/seek/ac3_rm
+++ b/tests/ref/seek/ac3_rm
@@ -5,11 +5,9 @@ ret:-1 st:-1 flags:1 ts: 1.894167
ret:-1 st: 0 flags:0 ts: 0.788000
ret: 0 st: 0 flags:1 ts:-0.317000
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
-ret: 0 st:-1 flags:0 ts: 2.576668
-ret: 0 st: 0 flags:1 dts: 4.179000 pts: 4.179000 pos: 68585 size: 556
+ret:-1 st:-1 flags:0 ts: 2.576668
ret:-1 st:-1 flags:1 ts: 1.470835
-ret: 0 st: 0 flags:0 ts: 0.365000
-ret: 0 st: 0 flags:1 dts: 0.383000 pts: 0.383000 pos: 6533 size: 558
+ret:-1 st: 0 flags:0 ts: 0.365000
ret: 0 st: 0 flags:1 ts:-0.741000
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
ret:-1 st:-1 flags:0 ts: 2.153336
@@ -18,25 +16,20 @@ ret: 0 st: 0 flags:0 ts:-0.058000
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
ret:-1 st: 0 flags:1 ts: 2.836000
ret:-1 st:-1 flags:0 ts: 1.730004
-ret: 0 st:-1 flags:1 ts: 0.624171
-ret: 0 st: 0 flags:1 dts: 0.452000 pts: 0.452000 pos: 7671 size: 558
+ret:-1 st:-1 flags:1 ts: 0.624171
ret: 0 st: 0 flags:0 ts:-0.482000
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
-ret: 0 st: 0 flags:1 ts: 2.413000
-ret: 0 st: 0 flags:1 dts: 2.333000 pts: 2.333000 pos: 38413 size: 556
+ret:-1 st: 0 flags:1 ts: 2.413000
ret:-1 st:-1 flags:0 ts: 1.306672
ret:-1 st:-1 flags:1 ts: 0.200839
ret: 0 st: 0 flags:0 ts:-0.905000
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
-ret: 0 st: 0 flags:1 ts: 1.989000
-ret: 0 st: 0 flags:1 dts: 1.985000 pts: 1.985000 pos: 32719 size: 558
+ret:-1 st: 0 flags:1 ts: 1.989000
ret:-1 st:-1 flags:0 ts: 0.883340
ret: 0 st:-1 flags:1 ts:-0.222493
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
-ret: 0 st: 0 flags:0 ts: 2.672000
-ret: 0 st: 0 flags:1 dts: 4.179000 pts: 4.179000 pos: 68585 size: 556
+ret:-1 st: 0 flags:0 ts: 2.672000
ret:-1 st: 0 flags:1 ts: 1.566000
-ret: 0 st:-1 flags:0 ts: 0.460008
-ret: 0 st: 0 flags:1 dts: 4.179000 pts: 4.179000 pos: 68585 size: 556
+ret:-1 st:-1 flags:0 ts: 0.460008
ret: 0 st:-1 flags:1 ts:-0.645825
ret: 0 st: 0 flags:1 dts: 0.000000 pts: 0.000000 pos: 271 size: 556
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-01 23:17:50 +0000