[FFmpeg-devel] [PATCH v7 2/3] libavcodec/flacenc: Implement encoding of 32 bit-per-sample PCM
Martijn van Beurden
mvanb1 at gmail.com
Tue Oct 11 20:24:36 EEST 2022
Add encoding of 32 bit-per-sample PCM to FLAC files to libavcodec.
Coding to this format is at this point considered experimental and
-strict experimental is needed to get ffmpeg to encode such files.
---
libavcodec/flacenc.c | 480 +++++++++++++++++++++++++++++++---------
libavcodec/put_bits.h | 7 +
libavcodec/put_golomb.h | 14 --
3 files changed, 379 insertions(+), 122 deletions(-)
diff --git a/libavcodec/flacenc.c b/libavcodec/flacenc.c
index 5d8c3f82be..1e4eb0d319 100644
--- a/libavcodec/flacenc.c
+++ b/libavcodec/flacenc.c
@@ -31,7 +31,6 @@
#include "codec_internal.h"
#include "encode.h"
#include "put_bits.h"
-#include "put_golomb.h"
#include "lpc.h"
#include "flac.h"
#include "flacdata.h"
@@ -95,6 +94,7 @@ typedef struct FlacSubframe {
typedef struct FlacFrame {
FlacSubframe subframes[FLAC_MAX_CHANNELS];
+ int64_t samples_33bps[FLAC_MAX_BLOCKSIZE];
int blocksize;
int bs_code[2];
uint8_t crc8;
@@ -282,10 +282,22 @@ static av_cold int flac_encode_init(AVCodecContext *avctx)
s->bps_code = 4;
break;
case AV_SAMPLE_FMT_S32:
- if (avctx->bits_per_raw_sample != 24)
- av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
- avctx->bits_per_raw_sample = 24;
- s->bps_code = 6;
+ if (avctx->bits_per_raw_sample <= 24) {
+ if (avctx->bits_per_raw_sample < 24)
+ av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
+ avctx->bits_per_raw_sample = 24;
+ s->bps_code = 6;
+ } else if (avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
+ av_log(avctx, AV_LOG_WARNING,
+ "encoding as 24 bits-per-sample, more is considered "
+ "experimental. Add -strict experimental if you want "
+ "to encode more than 24 bits-per-sample\n");
+ avctx->bits_per_raw_sample = 24;
+ s->bps_code = 6;
+ } else {
+ avctx->bits_per_raw_sample = 32;
+ s->bps_code = 7;
+ }
break;
}
@@ -533,8 +545,7 @@ static uint64_t rice_count_exact(const int32_t *res, int n, int k)
uint64_t count = 0;
for (i = 0; i < n; i++) {
- int32_t v = -2 * res[i] - 1;
- v ^= v >> 31;
+ unsigned v = ((unsigned)(res[i]) << 1) ^ (res[i] >> 31);
count += (v >> k) + 1 + k;
}
return count;
@@ -713,8 +724,8 @@ static uint64_t calc_rice_params(RiceContext *rc,
tmp_rc.coding_mode = rc->coding_mode;
- for (i = 0; i < n; i++)
- udata[i] = (2 * data[i]) ^ (data[i] >> 31);
+ for (i = pred_order; i < n; i++)
+ udata[i] = ((unsigned)(data[i]) << 1) ^ (data[i] >> 31);
calc_sum_top(pmax, exact ? kmax : 0, udata, n, pred_order, sums);
@@ -812,6 +823,130 @@ static void encode_residual_fixed(int32_t *res, const int32_t *smp, int n,
}
+/* These four functions check for every residual whether it can be
+ * contained in <INT32_MIN,INT32_MAX]. In case it doesn't, the
+ * function that called this function has to try something else.
+ * Each function is duplicated, once for int32_t input, once for
+ * int64_t input */
+#define ENCODE_RESIDUAL_FIXED_WITH_RESIDUAL_LIMIT() \
+{ \
+ for (int i = 0; i < order; i++) \
+ res[i] = smp[i]; \
+ if (order == 0) { \
+ for (int i = order; i < n; i++) { \
+ if (smp[i] == INT32_MIN) \
+ return 1; \
+ res[i] = smp[i]; \
+ } \
+ } else if (order == 1) { \
+ for (int i = order; i < n; i++) { \
+ int64_t res64 = (int64_t)smp[i] - smp[i-1]; \
+ if (res64 <= INT32_MIN || res64 > INT32_MAX) \
+ return 1; \
+ res[i] = res64; \
+ } \
+ } else if (order == 2) { \
+ for (int i = order; i < n; i++) { \
+ int64_t res64 = (int64_t)smp[i] - 2*(int64_t)smp[i-1] + smp[i-2]; \
+ if (res64 <= INT32_MIN || res64 > INT32_MAX) \
+ return 1; \
+ res[i] = res64; \
+ } \
+ } else if (order == 3) { \
+ for (int i = order; i < n; i++) { \
+ int64_t res64 = (int64_t)smp[i] - 3*(int64_t)smp[i-1] + 3*(int64_t)smp[i-2] - smp[i-3]; \
+ if (res64 <= INT32_MIN || res64 > INT32_MAX) \
+ return 1; \
+ res[i] = res64; \
+ } \
+ } else { \
+ for (int i = order; i < n; i++) { \
+ int64_t res64 = (int64_t)smp[i] - 4*(int64_t)smp[i-1] + 6*(int64_t)smp[i-2] - 4*(int64_t)smp[i-3] + smp[i-4]; \
+ if (res64 <= INT32_MIN || res64 > INT32_MAX) \
+ return 1; \
+ res[i] = res64; \
+ } \
+ } \
+ return 0; \
+}
+
+static int encode_residual_fixed_with_residual_limit(int32_t *res, const int32_t *smp,
+ int n, int order)
+{
+ ENCODE_RESIDUAL_FIXED_WITH_RESIDUAL_LIMIT();
+}
+
+
+static int encode_residual_fixed_with_residual_limit_33bps(int32_t *res, const int64_t *smp,
+ int n, int order)
+{
+ ENCODE_RESIDUAL_FIXED_WITH_RESIDUAL_LIMIT();
+}
+
+#define LPC_ENCODE_WITH_RESIDUAL_LIMIT() \
+{ \
+ for (int i = 0; i < order; i++) \
+ res[i] = smp[i]; \
+ for (int i = order; i < len; i++) { \
+ int64_t p = 0, tmp; \
+ for (int j = 0; j < order; j++) \
+ p += (int64_t)coefs[j]*smp[(i-1)-j]; \
+ p >>= shift; \
+ tmp = smp[i] - p; \
+ if (tmp <= INT32_MIN || tmp > INT32_MAX) \
+ return 1; \
+ res[i] = tmp; \
+ } \
+ return 0; \
+}
+
+static int lpc_encode_with_residual_limit(int32_t *res, const int32_t *smp, int len,
+ int order, int32_t *coefs, int shift)
+{
+ LPC_ENCODE_WITH_RESIDUAL_LIMIT();
+}
+
+static int lpc_encode_with_residual_limit_33bps(int32_t *res, const int64_t *smp, int len,
+ int order, int32_t *coefs, int shift)
+{
+ LPC_ENCODE_WITH_RESIDUAL_LIMIT();
+}
+
+static int lpc_encode_choose_datapath(FlacEncodeContext *s, int32_t bps,
+ int32_t *res, const int32_t *smp,
+ const int64_t *smp_33bps, int len,
+ int order, int32_t *coefs, int shift)
+{
+ uint64_t max_residual_value = 0;
+ int64_t max_sample_value = ((int64_t)(1) << (bps-1));
+ /* This calculates the max size of any residual with the current
+ * predictor, so we know whether we need to check the residual */
+ for (int i = 0; i < order; i++)
+ max_residual_value += FFABS(max_sample_value * coefs[i]);
+ max_residual_value >>= shift;
+ max_residual_value += max_sample_value;
+ if (bps > 32) {
+ if (lpc_encode_with_residual_limit_33bps(res, smp_33bps, len, order, coefs, shift))
+ return 1;
+ } else if (max_residual_value > INT32_MAX) {
+ if (lpc_encode_with_residual_limit(res, smp, len, order, coefs, shift))
+ return 1;
+ } else if (bps + s->options.lpc_coeff_precision + av_log2(order) <= 32) {
+ s->flac_dsp.lpc16_encode(res, smp, len, order, coefs, shift);
+ } else {
+ s->flac_dsp.lpc32_encode(res, smp, len, order, coefs, shift);
+ }
+ return 0;
+}
+
+#define DEFAULT_TO_VERBATIM() \
+{ \
+ sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM; \
+ if (sub->obits <= 32) \
+ memcpy(res, smp, n * sizeof(int32_t)); \
+ return subframe_count_exact(s, sub, 0); \
+}
+
static int encode_residual_ch(FlacEncodeContext *s, int ch)
{
int i, n;
@@ -821,28 +956,38 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
int32_t coefs[MAX_LPC_ORDER][MAX_LPC_ORDER];
int shift[MAX_LPC_ORDER];
int32_t *res, *smp;
+ int64_t *smp_33bps;
- frame = &s->frame;
- sub = &frame->subframes[ch];
- res = sub->residual;
- smp = sub->samples;
- n = frame->blocksize;
+ frame = &s->frame;
+ sub = &frame->subframes[ch];
+ res = sub->residual;
+ smp = sub->samples;
+ smp_33bps = frame->samples_33bps;
+ n = frame->blocksize;
/* CONSTANT */
- for (i = 1; i < n; i++)
- if(smp[i] != smp[0])
- break;
- if (i == n) {
- sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
- res[0] = smp[0];
- return subframe_count_exact(s, sub, 0);
+ if (sub->obits > 32) {
+ for (i = 1; i < n; i++)
+ if(smp_33bps[i] != smp_33bps[0])
+ break;
+ if (i == n) {
+ sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
+ return subframe_count_exact(s, sub, 0);
+ }
+ } else {
+ for (i = 1; i < n; i++)
+ if(smp[i] != smp[0])
+ break;
+ if (i == n) {
+ sub->type = sub->type_code = FLAC_SUBFRAME_CONSTANT;
+ res[0] = smp[0];
+ return subframe_count_exact(s, sub, 0);
+ }
}
/* VERBATIM */
if (frame->verbatim_only || n < 5) {
- sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
- memcpy(res, smp, n * sizeof(int32_t));
- return subframe_count_exact(s, sub, 0);
+ DEFAULT_TO_VERBATIM();
}
min_order = s->options.min_prediction_order;
@@ -859,15 +1004,32 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
opt_order = 0;
bits[0] = UINT32_MAX;
for (i = min_order; i <= max_order; i++) {
- encode_residual_fixed(res, smp, n, i);
+ if (sub->obits == 33) {
+ if (encode_residual_fixed_with_residual_limit_33bps(res, smp_33bps, n, i))
+ continue;
+ } else if (sub->obits + i >= 32) {
+ if (encode_residual_fixed_with_residual_limit(res, smp, n, i))
+ continue;
+ } else
+ encode_residual_fixed(res, smp, n, i);
bits[i] = find_subframe_rice_params(s, sub, i);
if (bits[i] < bits[opt_order])
opt_order = i;
}
+ if (opt_order == 0 && bits[0] == UINT32_MAX) {
+ /* No predictor found with residuals within <INT32_MIN,INT32_MAX],
+ * so encode a verbatim subframe instead */
+ DEFAULT_TO_VERBATIM();
+ }
sub->order = opt_order;
sub->type_code = sub->type | sub->order;
if (sub->order != max_order) {
- encode_residual_fixed(res, smp, n, sub->order);
+ if (sub->obits == 33)
+ encode_residual_fixed_with_residual_limit_33bps(res, smp_33bps, n, sub->order);
+ else if (sub->obits + i >= 32)
+ encode_residual_fixed_with_residual_limit(res, smp, n, sub->order);
+ else
+ encode_residual_fixed(res, smp, n, sub->order);
find_subframe_rice_params(s, sub, sub->order);
}
return subframe_count_exact(s, sub, sub->order);
@@ -875,6 +1037,14 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
/* LPC */
sub->type = FLAC_SUBFRAME_LPC;
+ if (sub->obits == 33)
+ /* As ff_lpc_calc_coefs is shared with other codecs and the LSB
+ * probably isn't predictable anyway, throw away LSB for analysis
+ * so it fits 32 bit int and existing function can be used
+ * unmodified */
+ for (i = 0; i < n; i++)
+ smp[i] = smp_33bps[i] >> 1;
+
opt_order = ff_lpc_calc_coefs(&s->lpc_ctx, smp, n, min_order, max_order,
s->options.lpc_coeff_precision, coefs, shift, s->options.lpc_type,
s->options.lpc_passes, omethod,
@@ -895,13 +1065,8 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
order = av_clip(order, min_order - 1, max_order - 1);
if (order == last_order)
continue;
- if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(order) <= 32) {
- s->flac_dsp.lpc16_encode(res, smp, n, order+1, coefs[order],
- shift[order]);
- } else {
- s->flac_dsp.lpc32_encode(res, smp, n, order+1, coefs[order],
- shift[order]);
- }
+ if(lpc_encode_choose_datapath(s, sub->obits, res, smp, smp_33bps, n, order+1, coefs[order], shift[order]))
+ continue;
bits[i] = find_subframe_rice_params(s, sub, order+1);
if (bits[i] < bits[opt_index]) {
opt_index = i;
@@ -915,11 +1080,8 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
opt_order = 0;
bits[0] = UINT32_MAX;
for (i = min_order-1; i < max_order; i++) {
- if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(i) <= 32) {
- s->flac_dsp.lpc16_encode(res, smp, n, i+1, coefs[i], shift[i]);
- } else {
- s->flac_dsp.lpc32_encode(res, smp, n, i+1, coefs[i], shift[i]);
- }
+ if(lpc_encode_choose_datapath(s, sub->obits, res, smp, smp_33bps, n, i+1, coefs[i], shift[i]))
+ continue;
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
@@ -937,11 +1099,8 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
for (i = last-step; i <= last+step; i += step) {
if (i < min_order-1 || i >= max_order || bits[i] < UINT32_MAX)
continue;
- if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(i) <= 32) {
- s->flac_dsp.lpc32_encode(res, smp, n, i+1, coefs[i], shift[i]);
- } else {
- s->flac_dsp.lpc16_encode(res, smp, n, i+1, coefs[i], shift[i]);
- }
+ if(lpc_encode_choose_datapath(s, sub->obits, res, smp, smp_33bps, n, i+1, coefs[i], shift[i]))
+ continue;
bits[i] = find_subframe_rice_params(s, sub, i+1);
if (bits[i] < bits[opt_order])
opt_order = i;
@@ -978,11 +1137,8 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
if (diffsum >8)
continue;
- if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(opt_order - 1) <= 32) {
- s->flac_dsp.lpc16_encode(res, smp, n, opt_order, lpc_try, shift[opt_order-1]);
- } else {
- s->flac_dsp.lpc32_encode(res, smp, n, opt_order, lpc_try, shift[opt_order-1]);
- }
+ if(lpc_encode_choose_datapath(s, sub->obits, res, smp, smp_33bps, n, opt_order, lpc_try, shift[opt_order-1]))
+ continue;
score = find_subframe_rice_params(s, sub, opt_order);
if (score < best_score) {
best_score = score;
@@ -999,10 +1155,10 @@ static int encode_residual_ch(FlacEncodeContext *s, int ch)
for (i = 0; i < sub->order; i++)
sub->coefs[i] = coefs[sub->order-1][i];
- if (s->bps_code * 4 + s->options.lpc_coeff_precision + av_log2(opt_order) <= 32) {
- s->flac_dsp.lpc16_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
- } else {
- s->flac_dsp.lpc32_encode(res, smp, n, sub->order, sub->coefs, sub->shift);
+ if(lpc_encode_choose_datapath(s, sub->obits, res, smp, smp_33bps, n, sub->order, sub->coefs, sub->shift)) {
+ /* No predictor found with residuals within <INT32_MIN,INT32_MAX],
+ * so encode a verbatim subframe instead */
+ DEFAULT_TO_VERBATIM();
}
find_subframe_rice_params(s, sub, sub->order);
@@ -1069,57 +1225,91 @@ static int encode_frame(FlacEncodeContext *s)
static void remove_wasted_bits(FlacEncodeContext *s)
{
- int ch, i;
+ int ch, i, wasted_bits;
for (ch = 0; ch < s->channels; ch++) {
FlacSubframe *sub = &s->frame.subframes[ch];
- int32_t v = 0;
- for (i = 0; i < s->frame.blocksize; i++) {
- v |= sub->samples[i];
- if (v & 1)
- break;
- }
+ if (sub->obits > 32) {
+ int64_t v = 0;
+ for (i = 0; i < s->frame.blocksize; i++) {
+ v |= s->frame.samples_33bps[i];
+ if (v & 1)
+ break;
+ }
+
+ if (!v || (v & 1))
+ return;
+
+ v = ff_ctzll(v);
+
+ /* If any wasted bits are found, samples are moved
+ * from frame.samples_33bps to frame.subframes[ch] */
+ for (i = 0; i < s->frame.blocksize; i++)
+ sub->samples[i] = s->frame.samples_33bps[i] >> v;
+ wasted_bits = v;
+ } else {
+ int32_t v = 0;
+ for (i = 0; i < s->frame.blocksize; i++) {
+ v |= sub->samples[i];
+ if (v & 1)
+ break;
+ }
+
+ if (!v || (v & 1))
+ return;
- if (v && !(v & 1)) {
v = ff_ctz(v);
for (i = 0; i < s->frame.blocksize; i++)
sub->samples[i] >>= v;
+ wasted_bits = v;
+ }
- sub->wasted = v;
- sub->obits -= v;
+ sub->wasted = wasted_bits;
+ sub->obits -= wasted_bits;
- /* for 24-bit, check if removing wasted bits makes the range better
- suited for using RICE instead of RICE2 for entropy coding */
- if (sub->obits <= 17)
- sub->rc.coding_mode = CODING_MODE_RICE;
- }
+ /* for 24-bit, check if removing wasted bits makes the range better
+ * suited for using RICE instead of RICE2 for entropy coding */
+ if (sub->obits <= 17)
+ sub->rc.coding_mode = CODING_MODE_RICE;
}
}
static int estimate_stereo_mode(const int32_t *left_ch, const int32_t *right_ch, int n,
- int max_rice_param)
+ int max_rice_param, int bps)
{
- int i, best;
- int32_t lt, rt;
+ int best;
uint64_t sum[4];
uint64_t score[4];
int k;
/* calculate sum of 2nd order residual for each channel */
sum[0] = sum[1] = sum[2] = sum[3] = 0;
- for (i = 2; i < n; i++) {
- lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
- rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
- sum[2] += FFABS((lt + rt) >> 1);
- sum[3] += FFABS(lt - rt);
- sum[0] += FFABS(lt);
- sum[1] += FFABS(rt);
+ if(bps < 30) {
+ int32_t lt, rt;
+ for (int i = 2; i < n; i++) {
+ lt = left_ch[i] - 2*left_ch[i-1] + left_ch[i-2];
+ rt = right_ch[i] - 2*right_ch[i-1] + right_ch[i-2];
+ sum[2] += FFABS((lt + rt) >> 1);
+ sum[3] += FFABS(lt - rt);
+ sum[0] += FFABS(lt);
+ sum[1] += FFABS(rt);
+ }
+ } else {
+ int64_t lt, rt;
+ for (int i = 2; i < n; i++) {
+ lt = (int64_t)left_ch[i] - 2*(int64_t)left_ch[i-1] + left_ch[i-2];
+ rt = (int64_t)right_ch[i] - 2*(int64_t)right_ch[i-1] + right_ch[i-2];
+ sum[2] += FFABS((lt + rt) >> 1);
+ sum[3] += FFABS(lt - rt);
+ sum[0] += FFABS(lt);
+ sum[1] += FFABS(rt);
+ }
}
/* estimate bit counts */
- for (i = 0; i < 4; i++) {
+ for (int i = 0; i < 4; i++) {
k = find_optimal_param(2 * sum[i], n, max_rice_param);
sum[i] = rice_encode_count( 2 * sum[i], n, k);
}
@@ -1132,7 +1322,7 @@ static int estimate_stereo_mode(const int32_t *left_ch, const int32_t *right_ch,
/* return mode with lowest score */
best = 0;
- for (i = 1; i < 4; i++)
+ for (int i = 1; i < 4; i++)
if (score[i] < score[best])
best = i;
@@ -1147,12 +1337,14 @@ static void channel_decorrelation(FlacEncodeContext *s)
{
FlacFrame *frame;
int32_t *left, *right;
- int i, n;
+ int64_t *side_33bps;
+ int n;
- frame = &s->frame;
- n = frame->blocksize;
- left = frame->subframes[0].samples;
- right = frame->subframes[1].samples;
+ frame = &s->frame;
+ n = frame->blocksize;
+ left = frame->subframes[0].samples;
+ right = frame->subframes[1].samples;
+ side_33bps = frame->samples_33bps;
if (s->channels != 2) {
frame->ch_mode = FLAC_CHMODE_INDEPENDENT;
@@ -1161,29 +1353,49 @@ static void channel_decorrelation(FlacEncodeContext *s)
if (s->options.ch_mode < 0) {
int max_rice_param = (1 << frame->subframes[0].rc.coding_mode) - 2;
- frame->ch_mode = estimate_stereo_mode(left, right, n, max_rice_param);
+ frame->ch_mode = estimate_stereo_mode(left, right, n, max_rice_param, s->avctx->bits_per_raw_sample);
} else
frame->ch_mode = s->options.ch_mode;
/* perform decorrelation and adjust bits-per-sample */
if (frame->ch_mode == FLAC_CHMODE_INDEPENDENT)
return;
- if (frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
- int32_t tmp;
- for (i = 0; i < n; i++) {
- tmp = left[i];
- left[i] = (tmp + right[i]) >> 1;
- right[i] = tmp - right[i];
+ if(s->avctx->bits_per_raw_sample == 32) {
+ if (frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
+ int64_t tmp;
+ for (int i = 0; i < n; i++) {
+ tmp = left[i];
+ left[i] = (tmp + right[i]) >> 1;
+ side_33bps[i] = tmp - right[i];
+ }
+ frame->subframes[1].obits++;
+ } else if (frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
+ for (int i = 0; i < n; i++)
+ side_33bps[i] = (int64_t)left[i] - right[i];
+ frame->subframes[1].obits++;
+ } else {
+ for (int i = 0; i < n; i++)
+ side_33bps[i] = (int64_t)left[i] - right[i];
+ frame->subframes[0].obits++;
}
- frame->subframes[1].obits++;
- } else if (frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
- for (i = 0; i < n; i++)
- right[i] = left[i] - right[i];
- frame->subframes[1].obits++;
} else {
- for (i = 0; i < n; i++)
- left[i] -= right[i];
- frame->subframes[0].obits++;
+ if (frame->ch_mode == FLAC_CHMODE_MID_SIDE) {
+ int32_t tmp;
+ for (int i = 0; i < n; i++) {
+ tmp = left[i];
+ left[i] = (tmp + right[i]) >> 1;
+ right[i] = tmp - right[i];
+ }
+ frame->subframes[1].obits++;
+ } else if (frame->ch_mode == FLAC_CHMODE_LEFT_SIDE) {
+ for (int i = 0; i < n; i++)
+ right[i] = left[i] - right[i];
+ frame->subframes[1].obits++;
+ } else {
+ for (int i = 0; i < n; i++)
+ left[i] -= right[i];
+ frame->subframes[0].obits++;
+ }
}
}
@@ -1232,13 +1444,32 @@ static void write_frame_header(FlacEncodeContext *s)
}
+static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k)
+{
+ unsigned v, e;
+
+ v = ((unsigned)(i) << 1) ^ (i >> 31);
+
+ e = (v >> k) + 1;
+ while (e > 31) {
+ put_bits(pb, 31, 0);
+ e -= 31;
+ }
+ put_bits(pb, e, 1);
+ if (k) {
+ unsigned mask = UINT32_MAX >> (32-k);
+ put_bits(pb, k, v & mask);
+ }
+}
+
+
static void write_subframes(FlacEncodeContext *s)
{
int ch;
for (ch = 0; ch < s->channels; ch++) {
FlacSubframe *sub = &s->frame.subframes[ch];
- int i, p, porder, psize;
+ int p, porder, psize;
int32_t *part_end;
int32_t *res = sub->residual;
int32_t *frame_end = &sub->residual[s->frame.blocksize];
@@ -1252,21 +1483,45 @@ static void write_subframes(FlacEncodeContext *s)
/* subframe */
if (sub->type == FLAC_SUBFRAME_CONSTANT) {
- put_sbits(&s->pb, sub->obits, res[0]);
+ if(sub->obits == 33)
+ put_sbits63(&s->pb, 33, s->frame.samples_33bps[0]);
+ else if(sub->obits == 32)
+ put_bits32(&s->pb, res[0]);
+ else
+ put_sbits(&s->pb, sub->obits, res[0]);
} else if (sub->type == FLAC_SUBFRAME_VERBATIM) {
- while (res < frame_end)
- put_sbits(&s->pb, sub->obits, *res++);
+ if (sub->obits == 33) {
+ int64_t *res64 = s->frame.samples_33bps;
+ int64_t *frame_end64 = &s->frame.samples_33bps[s->frame.blocksize];
+ while (res64 < frame_end64)
+ put_sbits63(&s->pb, 33, (*res64++));
+ } else if (sub->obits == 32) {
+ while (res < frame_end)
+ put_bits32(&s->pb, *res++);
+ } else {
+ while (res < frame_end)
+ put_sbits(&s->pb, sub->obits, *res++);
+ }
} else {
/* warm-up samples */
- for (i = 0; i < sub->order; i++)
- put_sbits(&s->pb, sub->obits, *res++);
+ if (sub->obits == 33) {
+ for (int i = 0; i < sub->order; i++)
+ put_sbits63(&s->pb, 33, s->frame.samples_33bps[i]);
+ res += sub->order;
+ } else if (sub->obits == 32) {
+ for (int i = 0; i < sub->order; i++)
+ put_bits32(&s->pb, *res++);
+ } else {
+ for (int i = 0; i < sub->order; i++)
+ put_sbits(&s->pb, sub->obits, *res++);
+ }
/* LPC coefficients */
if (sub->type == FLAC_SUBFRAME_LPC) {
int cbits = s->options.lpc_coeff_precision;
put_bits( &s->pb, 4, cbits-1);
put_sbits(&s->pb, 5, sub->shift);
- for (i = 0; i < sub->order; i++)
+ for (int i = 0; i < sub->order; i++)
put_sbits(&s->pb, cbits, sub->coefs[i]);
}
@@ -1284,7 +1539,7 @@ static void write_subframes(FlacEncodeContext *s)
int k = sub->rc.params[p];
put_bits(&s->pb, sub->rc.coding_mode, k);
while (res < part_end)
- set_sr_golomb_flac(&s->pb, *res++, k, INT32_MAX, 0);
+ set_sr_golomb_flac(&s->pb, *res++, k);
part_end = FFMIN(frame_end, part_end + psize);
}
}
@@ -1332,7 +1587,7 @@ static int update_md5_sum(FlacEncodeContext *s, const void *samples)
(const uint16_t *) samples, buf_size / 2);
buf = s->md5_buffer;
#endif
- } else {
+ } else if (s->avctx->bits_per_raw_sample <= 24) {
int i;
const int32_t *samples0 = samples;
uint8_t *tmp = s->md5_buffer;
@@ -1342,6 +1597,15 @@ static int update_md5_sum(FlacEncodeContext *s, const void *samples)
AV_WL24(tmp + 3*i, v);
}
buf = s->md5_buffer;
+ } else {
+ /* s->avctx->bits_per_raw_sample <= 32 */
+ int i;
+ const int32_t *samples0 = samples;
+ uint8_t *tmp = s->md5_buffer;
+
+ for (i = 0; i < s->frame.blocksize * s->channels; i++)
+ AV_WL32(tmp + 4*i, samples0[i]);
+ buf = s->md5_buffer;
}
av_md5_update(s->md5ctx, buf, buf_size);
diff --git a/libavcodec/put_bits.h b/libavcodec/put_bits.h
index 4b4f977ad5..4561dc131a 100644
--- a/libavcodec/put_bits.h
+++ b/libavcodec/put_bits.h
@@ -363,6 +363,13 @@ static inline void put_bits64(PutBitContext *s, int n, uint64_t value)
}
}
+static inline void put_sbits63(PutBitContext *pb, int n, int64_t value)
+{
+ av_assert2(n >= 0 && n < 64);
+
+ put_bits64(pb, n, (uint64_t)(value) & (~(UINT64_MAX << n)));
+}
+
/**
* Return the pointer to the byte where the bitstream writer will put
* the next bit.
diff --git a/libavcodec/put_golomb.h b/libavcodec/put_golomb.h
index 9ca911fc3c..df47fd2c0a 100644
--- a/libavcodec/put_golomb.h
+++ b/libavcodec/put_golomb.h
@@ -151,18 +151,4 @@ static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit,
set_ur_golomb(pb, v, k, limit, esc_len);
}
-/**
- * write signed golomb rice code (flac).
- */
-static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k,
- int limit, int esc_len)
-{
- int v;
-
- v = -2 * i - 1;
- v ^= (v >> 31);
-
- set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
-}
-
#endif /* AVCODEC_PUT_GOLOMB_H */
--
2.30.2
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