#define FLAC_STREAMINFO_SIZE 34
+typedef struct RiceContext {
+ int porder;
+ int params[256];
+} RiceContext;
+
typedef struct FlacSubframe {
int type;
int type_code;
int obits;
int order;
+ RiceContext rc;
int32_t samples[FLAC_MAX_BLOCKSIZE];
int32_t residual[FLAC_MAX_BLOCKSIZE];
} FlacSubframe;
int max_framesize;
uint32_t frame_count;
FlacFrame frame;
+ AVCodecContext *avctx;
} FlacEncodeContext;
static const int flac_samplerates[16] = {
/* MD5 signature = 0 */
}
-#define BLOCK_TIME_MS 105
+#define BLOCK_TIME_MS 27
/**
* Sets blocksize based on samplerate
int i;
uint8_t *streaminfo;
+ s->avctx = avctx;
+
if(avctx->sample_fmt != SAMPLE_FMT_S16) {
return -1;
}
}
}
+
+#define rice_encode_count(sum, n, k) (((n)*((k)+1))+((sum-(n>>1))>>(k)))
+
+static int find_optimal_param(uint32_t sum, int n)
+{
+ int k, k_opt;
+ uint32_t nbits, nbits_opt;
+
+ k_opt = 0;
+ nbits_opt = rice_encode_count(sum, n, 0);
+ for(k=1; k<=14; k++) {
+ nbits = rice_encode_count(sum, n, k);
+ if(nbits < nbits_opt) {
+ nbits_opt = nbits;
+ k_opt = k;
+ }
+ }
+ return k_opt;
+}
+
+static uint32_t calc_optimal_rice_params(RiceContext *rc, int porder,
+ uint32_t *sums, int n, int pred_order)
+{
+ int i;
+ int k, cnt, part;
+ uint32_t all_bits;
+
+ part = (1 << porder);
+ all_bits = 0;
+
+ cnt = (n >> porder) - pred_order;
+ for(i=0; i<part; i++) {
+ if(i == 1) cnt = (n >> porder);
+ k = find_optimal_param(sums[i], cnt);
+ rc->params[i] = k;
+ all_bits += rice_encode_count(sums[i], cnt, k);
+ }
+ all_bits += (4 * part);
+
+ rc->porder = porder;
+
+ return all_bits;
+}
+
+static void calc_sums(int pmax, uint32_t *data, int n, int pred_order,
+ uint32_t sums[][256])
+{
+ int i, j;
+ int parts, cnt;
+ uint32_t *res;
+
+ /* sums for highest level */
+ parts = (1 << pmax);
+ res = &data[pred_order];
+ cnt = (n >> pmax) - pred_order;
+ for(i=0; i<parts; i++) {
+ if(i == 1) cnt = (n >> pmax);
+ if(i > 0) res = &data[i*cnt];
+ sums[pmax][i] = 0;
+ for(j=0; j<cnt; j++) {
+ sums[pmax][i] += res[j];
+ }
+ }
+ /* sums for lower levels */
+ for(i=pmax-1; i>=0; i--) {
+ parts = (1 << i);
+ for(j=0; j<parts; j++) {
+ sums[i][j] = sums[i+1][2*j] + sums[i+1][2*j+1];
+ }
+ }
+}
+
+static uint32_t calc_rice_params(RiceContext *rc, int pmax, int32_t *data,
+ int n, int pred_order)
+{
+ int i;
+ uint32_t bits, opt_bits;
+ int opt_porder;
+ RiceContext opt_rc;
+ uint32_t *udata;
+ uint32_t sums[9][256];
+
+ assert(pmax >= 0 && pmax <= 8);
+
+ udata = av_malloc(n * sizeof(uint32_t));
+ for(i=0; i<n; i++) {
+ udata[i] = (2*data[i]) ^ (data[i]>>31);
+ }
+
+ calc_sums(pmax, udata, n, pred_order, sums);
+
+ opt_porder = 0;
+ opt_bits = UINT32_MAX;
+ for(i=0; i<=pmax; i++) {
+ bits = calc_optimal_rice_params(rc, i, sums[i], n, pred_order);
+ if(bits < opt_bits) {
+ opt_bits = bits;
+ opt_porder = i;
+ memcpy(&opt_rc, rc, sizeof(RiceContext));
+ }
+ }
+ if(opt_porder != pmax) {
+ memcpy(rc, &opt_rc, sizeof(RiceContext));
+ }
+
+ av_freep(&udata);
+ return opt_bits;
+}
+
+static uint32_t calc_rice_params_fixed(RiceContext *rc, int pmax, int32_t *data,
+ int n, int pred_order, int bps)
+{
+ uint32_t bits;
+ bits = pred_order*bps + 6;
+ bits += calc_rice_params(rc, pmax, data, n, pred_order);
+ return bits;
+}
+
+static void encode_residual_verbatim(int32_t *res, int32_t *smp, int n)
+{
+ assert(n > 0);
+ memcpy(res, smp, n * sizeof(int32_t));
+}
+
+static void encode_residual_fixed(int32_t *res, int32_t *smp, int n, int order)
+{
+ int i;
+
+ for(i=0; i<order; i++) {
+ res[i] = smp[i];
+ }
+
+ if(order==0){
+ for(i=order; i<n; i++)
+ res[i]= smp[i];
+ }else if(order==1){
+ for(i=order; i<n; i++)
+ res[i]= smp[i] - smp[i-1];
+ }else if(order==2){
+ for(i=order; i<n; i++)
+ res[i]= smp[i] - 2*smp[i-1] + smp[i-2];
+ }else if(order==3){
+ for(i=order; i<n; i++)
+ res[i]= smp[i] - 3*smp[i-1] + 3*smp[i-2] - smp[i-3];
+ }else{
+ for(i=order; i<n; i++)
+ res[i]= smp[i] - 4*smp[i-1] + 6*smp[i-2] - 4*smp[i-3] + smp[i-4];
+ }
+}
+
+static int get_max_p_order(int max_porder, int n, int order)
+{
+ int porder, max_parts;
+
+ porder = max_porder;
+ while(porder > 0) {
+ max_parts = (1 << porder);
+ if(!(n % max_parts) && (n > max_parts*order)) {
+ break;
+ }
+ porder--;
+ }
+ return porder;
+}
+
+static int encode_residual(FlacEncodeContext *ctx, int ch)
+{
+ int i, opt_order, porder, max_porder, n;
+ FlacFrame *frame;
+ FlacSubframe *sub;
+ uint32_t bits[5];
+ int32_t *res, *smp;
+
+ frame = &ctx->frame;
+ sub = &frame->subframes[ch];
+ res = sub->residual;
+ smp = sub->samples;
+ 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 sub->obits;
+ }
+
+ /* VERBATIM */
+ if(n < 5) {
+ sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
+ encode_residual_verbatim(res, smp, n);
+ return sub->obits * n;
+ }
+
+ max_porder = 3;
+
+ /* FIXED */
+ opt_order = 0;
+ bits[0] = UINT32_MAX;
+ for(i=0; i<=4; i++) {
+ encode_residual_fixed(res, smp, n, i);
+ porder = get_max_p_order(max_porder, n, i);
+ bits[i] = calc_rice_params_fixed(&sub->rc, porder, res, n, i, sub->obits);
+ if(bits[i] < bits[opt_order]) {
+ opt_order = i;
+ }
+ }
+ sub->order = opt_order;
+ sub->type = FLAC_SUBFRAME_FIXED;
+ sub->type_code = sub->type | sub->order;
+ if(sub->order != 4) {
+ encode_residual_fixed(res, smp, n, sub->order);
+ porder = get_max_p_order(max_porder, n, sub->order);
+ calc_rice_params_fixed(&sub->rc, porder, res, n, sub->order, sub->obits);
+ }
+ return bits[sub->order];
+}
+
+static int encode_residual_v(FlacEncodeContext *ctx, int ch)
+{
+ int i, n;
+ FlacFrame *frame;
+ FlacSubframe *sub;
+ int32_t *res, *smp;
+
+ frame = &ctx->frame;
+ sub = &frame->subframes[ch];
+ res = sub->residual;
+ smp = sub->samples;
+ 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 sub->obits;
+ }
+
+ /* VERBATIM */
+ sub->type = sub->type_code = FLAC_SUBFRAME_VERBATIM;
+ encode_residual_verbatim(res, smp, n);
+ return sub->obits * n;
+}
+
static int estimate_stereo_mode(int32_t *left_ch, int32_t *right_ch, int n)
{
int i, best;
int32_t lt, rt;
- uint64_t left, right, mid, side;
+ uint64_t sum[4];
uint64_t score[4];
+ int k;
/* calculate sum of squares for each channel */
- left = right = mid = side = 0;
+ 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];
- mid += ABS((lt + rt) >> 1);
- side += ABS(lt - rt);
- left += ABS(lt);
- right += ABS(rt);
+ sum[2] += ABS((lt + rt) >> 1);
+ sum[3] += ABS(lt - rt);
+ sum[0] += ABS(lt);
+ sum[1] += ABS(rt);
+ }
+ for(i=0; i<4; i++) {
+ k = find_optimal_param(2*sum[i], n);
+ sum[i] = rice_encode_count(2*sum[i], n, k);
}
/* calculate score for each mode */
- score[0] = left + right;
- score[1] = left + side;
- score[2] = right + side;
- score[3] = mid + side;
+ score[0] = sum[0] + sum[1];
+ score[1] = sum[0] + sum[3];
+ score[2] = sum[1] + sum[3];
+ score[3] = sum[2] + sum[3];
/* return mode with lowest score */
best = 0;
}
}
-static void encode_residual_verbatim(FlacEncodeContext *s, int ch)
-{
- FlacFrame *frame;
- FlacSubframe *sub;
- int32_t *res;
- int32_t *smp;
- int n;
-
- frame = &s->frame;
- sub = &frame->subframes[ch];
- res = sub->residual;
- smp = sub->samples;
- n = frame->blocksize;
-
- sub->order = 0;
- sub->type = FLAC_SUBFRAME_VERBATIM;
- sub->type_code = sub->type;
-
- memcpy(res, smp, n * sizeof(int32_t));
-}
-
-static void encode_residual_fixed(int32_t *res, int32_t *smp, int n, int order)
-{
- int i;
-
- for(i=0; i<order; i++) {
- res[i] = smp[i];
- }
-
- if(order==0){
- for(i=order; i<n; i++)
- res[i]= smp[i];
- }else if(order==1){
- for(i=order; i<n; i++)
- res[i]= smp[i] - smp[i-1];
- }else if(order==2){
- for(i=order; i<n; i++)
- res[i]= smp[i] - 2*smp[i-1] + smp[i-2];
- }else if(order==3){
- for(i=order; i<n; i++)
- res[i]= smp[i] - 3*smp[i-1] + 3*smp[i-2] - smp[i-3];
- }else{
- for(i=order; i<n; i++)
- res[i]= smp[i] - 4*smp[i-1] + 6*smp[i-2] - 4*smp[i-3] + smp[i-4];
- }
-}
-
-static void encode_residual(FlacEncodeContext *s, int ch)
-{
- FlacFrame *frame;
- FlacSubframe *sub;
- int32_t *res;
- int32_t *smp;
- int n;
-
- frame = &s->frame;
- sub = &frame->subframes[ch];
- res = sub->residual;
- smp = sub->samples;
- n = frame->blocksize;
-
- sub->order = 2;
- sub->type = FLAC_SUBFRAME_FIXED;
- sub->type_code = sub->type | sub->order;
- encode_residual_fixed(res, smp, n, sub->order);
-}
-
-static void
-put_sbits(PutBitContext *pb, int bits, int32_t val)
+static void put_sbits(PutBitContext *pb, int bits, int32_t val)
{
assert(bits >= 0 && bits <= 31);
put_bits(pb, bits, val & ((1<<bits)-1));
}
-static void
-write_utf8(PutBitContext *pb, uint32_t val)
+static void write_utf8(PutBitContext *pb, uint32_t val)
{
int bytes, shift;
}
}
-static void
-output_frame_header(FlacEncodeContext *s)
+static void output_frame_header(FlacEncodeContext *s)
{
FlacFrame *frame;
int crc;
put_bits(&s->pb, 8, crc);
}
+static void output_subframe_constant(FlacEncodeContext *s, int ch)
+{
+ FlacSubframe *sub;
+ int32_t res;
+
+ sub = &s->frame.subframes[ch];
+ res = sub->residual[0];
+ put_sbits(&s->pb, sub->obits, res);
+}
+
static void output_subframe_verbatim(FlacEncodeContext *s, int ch)
{
int i;
}
}
-static void
-output_residual(FlacEncodeContext *ctx, int ch)
+static void output_residual(FlacEncodeContext *ctx, int ch)
{
- int i, j, p;
+ int i, j, p, n, parts;
int k, porder, psize, res_cnt;
FlacFrame *frame;
FlacSubframe *sub;
+ int32_t *res;
frame = &ctx->frame;
sub = &frame->subframes[ch];
+ res = sub->residual;
+ n = frame->blocksize;
/* rice-encoded block */
put_bits(&ctx->pb, 2, 0);
/* partition order */
- porder = 0;
- psize = frame->blocksize;
- //porder = sub->rc.porder;
- //psize = frame->blocksize >> porder;
+ porder = sub->rc.porder;
+ psize = n >> porder;
+ parts = (1 << porder);
put_bits(&ctx->pb, 4, porder);
res_cnt = psize - sub->order;
/* residual */
j = sub->order;
- for(p=0; p<(1 << porder); p++) {
- //k = sub->rc.params[p];
- k = 9;
+ for(p=0; p<parts; p++) {
+ k = sub->rc.params[p];
put_bits(&ctx->pb, 4, k);
if(p == 1) res_cnt = psize;
- for(i=0; i<res_cnt && j<frame->blocksize; i++, j++) {
- set_sr_golomb_flac(&ctx->pb, sub->residual[j], k, INT32_MAX, 0);
+ for(i=0; i<res_cnt && j<n; i++, j++) {
+ set_sr_golomb_flac(&ctx->pb, res[j], k, INT32_MAX, 0);
}
}
}
-static void
-output_subframe_fixed(FlacEncodeContext *ctx, int ch)
+static void output_subframe_fixed(FlacEncodeContext *ctx, int ch)
{
int i;
FlacFrame *frame;
put_bits(&s->pb, 1, 0); /* no wasted bits */
/* subframe */
- if(sub->type == FLAC_SUBFRAME_VERBATIM) {
+ if(sub->type == FLAC_SUBFRAME_CONSTANT) {
+ output_subframe_constant(s, ch);
+ } else if(sub->type == FLAC_SUBFRAME_VERBATIM) {
output_subframe_verbatim(s, ch);
- } else {
+ } else if(sub->type == FLAC_SUBFRAME_FIXED) {
output_subframe_fixed(s, ch);
}
}
if(out_bytes > s->max_framesize || out_bytes >= buf_size) {
/* frame too large. use verbatim mode */
for(ch=0; ch<s->channels; ch++) {
- encode_residual_verbatim(s, ch);
+ encode_residual_v(s, ch);
}
init_put_bits(&s->pb, frame, buf_size);
output_frame_header(s);