[FFmpeg-devel] [PATCH 2/2] aacenc: cosmetics, whitespace and comment clarification

Nathan Caldwell saintdev
Tue Mar 8 11:32:41 CET 2011


Correct bad indentation in aaccoder
Clarify and correct comments in 3GPP psymodel, other cosmetics.
---
 libavcodec/aaccoder.c |   50 ++++++++++++++++++++++++------------------------
 libavcodec/aacpsy.c   |   21 +++++++++++--------
 2 files changed, 37 insertions(+), 34 deletions(-)

diff --git a/libavcodec/aaccoder.c b/libavcodec/aaccoder.c
index 8063fb6..1db7bd3 100644
--- a/libavcodec/aaccoder.c
+++ b/libavcodec/aaccoder.c
@@ -146,34 +146,34 @@ static av_always_inline float
quantize_and_encode_band_cost_template(
             curidx *= range;
             curidx += quants[j] + off;
         }
-            curbits =  ff_aac_spectral_bits[cb-1][curidx];
-            vec     = &ff_aac_codebook_vectors[cb-1][curidx*dim];
-            if (BT_UNSIGNED) {
-                for (k = 0; k < dim; k++) {
-                    float t = fabsf(in[i+k]);
-                    float di;
-                    if (BT_ESC && vec[k] == 64.0f) { //FIXME: slow
-                        if (t >= CLIPPED_ESCAPE) {
-                            di = t - CLIPPED_ESCAPE;
-                            curbits += 21;
-                        } else {
-                            int c = av_clip(quant(t, Q), 0, 8191);
-                            di = t - c*cbrtf(c)*IQ;
-                            curbits += av_log2(c)*2 - 4 + 1;
-                        }
+        curbits =  ff_aac_spectral_bits[cb-1][curidx];
+        vec     = &ff_aac_codebook_vectors[cb-1][curidx*dim];
+        if (BT_UNSIGNED) {
+            for (k = 0; k < dim; k++) {
+                float t = fabsf(in[i+k]);
+                float di;
+                if (BT_ESC && vec[k] == 64.0f) { //FIXME: slow
+                    if (t >= CLIPPED_ESCAPE) {
+                        di = t - CLIPPED_ESCAPE;
+                        curbits += 21;
                     } else {
-                        di = t - vec[k]*IQ;
+                        int c = av_clip(quant(t, Q), 0, 8191);
+                        di = t - c*cbrtf(c)*IQ;
+                        curbits += av_log2(c)*2 - 4 + 1;
                     }
-                    if (vec[k] != 0.0f)
-                        curbits++;
-                    rd += di*di;
-                }
-            } else {
-                for (k = 0; k < dim; k++) {
-                    float di = in[i+k] - vec[k]*IQ;
-                    rd += di*di;
+                } else {
+                    di = t - vec[k]*IQ;
                 }
+                if (vec[k] != 0.0f)
+                    curbits++;
+                rd += di*di;
             }
+        } else {
+            for (k = 0; k < dim; k++) {
+                float di = in[i+k] - vec[k]*IQ;
+                rd += di*di;
+            }
+        }
         cost    += rd * lambda + curbits;
         resbits += curbits;
         if (cost >= uplim)
@@ -575,7 +575,7 @@ static void
search_for_quantizers_anmr(AVCodecContext *avctx, AACEncContext *s,
         int qnrg = av_clip_uint8(log2f(sqrtf(qnrgf/qcnt))*4 - 31 +
SCALE_ONE_POS - SCALE_DIV_512);
         q1 = qnrg + 30;
         q0 = qnrg - 30;
-    //av_log(NULL, AV_LOG_ERROR, "q0 %d, q1 %d\n", q0, q1);
+        //av_log(NULL, AV_LOG_ERROR, "q0 %d, q1 %d\n", q0, q1);
         if (q0 < q0low) {
             q1 += q0low - q0;
             q0  = q0low;
diff --git a/libavcodec/aacpsy.c b/libavcodec/aacpsy.c
index de3b0f3..d9896ed 100644
--- a/libavcodec/aacpsy.c
+++ b/libavcodec/aacpsy.c
@@ -39,8 +39,8 @@
  * constants for 3GPP AAC psychoacoustic model
  * @{
  */
-#define PSY_3GPP_SPREAD_HI   1.5f // spreading factor for ascending
threshold spreading  (15 dB/Bark)
-#define PSY_3GPP_SPREAD_LOW  3.0f // spreading factor for descending
threshold spreading (30 dB/Bark)
+#define PSY_3GPP_THR_SPREAD_HI   1.5f // spreading factor for
low-to-hi threshold spreading  (15 dB/Bark)
+#define PSY_3GPP_THR_SPREAD_LOW  3.0f // spreading factor for
hi-to-low threshold spreading  (30 dB/Bark)

 #define PSY_3GPP_RPEMIN      0.01f
 #define PSY_3GPP_RPELEV      2.0f
@@ -256,8 +256,8 @@ static av_cold int psy_3gpp_init(FFPsyContext *ctx) {
         for (g = 0; g < ctx->num_bands[j] - 1; g++) {
             AacPsyCoeffs *coeff = &coeffs[g];
             float bark_width = coeffs[g+1].barks - coeffs->barks;
-            coeff->spread_low[0] = pow(10.0, -bark_width *
PSY_3GPP_SPREAD_LOW);
-            coeff->spread_hi [0] = pow(10.0, -bark_width * PSY_3GPP_SPREAD_HI);
+            coeff->spread_low[0] = pow(10.0, -bark_width *
PSY_3GPP_THR_SPREAD_LOW);
+            coeff->spread_hi [0] = pow(10.0, -bark_width *
PSY_3GPP_THR_SPREAD_HI);
         }
         start = 0;
         for (g = 0; g < ctx->num_bands[j]; g++) {
@@ -395,9 +395,9 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
     AacPsyChannel *pch  = &pctx->ch[channel];
     int start = 0;
     int i, w, g;
-    const int num_bands       = ctx->num_bands[wi->num_windows == 8];
-    const uint8_t* band_sizes = ctx->bands[wi->num_windows == 8];
-    AacPsyCoeffs *coeffs     = &pctx->psy_coef[wi->num_windows == 8];
+    const int      num_bands  = ctx->num_bands[wi->num_windows == 8];
+    const uint8_t *band_sizes = ctx->bands[wi->num_windows == 8];
+    AacPsyCoeffs  *coeffs     = &pctx->psy_coef[wi->num_windows == 8];

     //calculate energies, initial thresholds and related values -
5.4.2 "Threshold Calculation"
     for (w = 0; w < wi->num_windows*16; w += 16) {
@@ -410,17 +410,19 @@ static void psy_3gpp_analyze(FFPsyContext *ctx,
int channel,
             start        += band_sizes[g];
         }
     }
-    //modify thresholds - spread, threshold in quiet - 5.4.3
"Spreaded Energy Calculation"
+    //modify thresholds and energies - spread, threshold in quiet,
pre-echo control
     for (w = 0; w < wi->num_windows*16; w += 16) {
-
         AacPsyBand *bands = &pch->band[w];
+        //5.4.2.3 "Spreading" & 5.4.3 "Spreaded Energy Calculation"
         for (g = 1; g < num_bands; g++)
             bands[g].thr = FFMAX(bands[g].thr, bands[g-1].thr *
coeffs[g].spread_hi[0]);
         for (g = num_bands - 2; g >= 0; g--)
             bands[g].thr = FFMAX(bands[g].thr, bands[g+1].thr *
coeffs[g].spread_low[0]);
+        //5.4.2.4 "Threshold in quiet"
         for (g = 0; g < num_bands; g++) {
             AacPsyBand *band = &bands[g];
             band->thr_quiet = band->thr = FFMAX(band->thr, coeffs[g].ath);
+            //5.4.2.5 "Pre-echo control"
             if (!(wi->window_type[0] == LONG_STOP_SEQUENCE ||
(wi->window_type[1] == LONG_START_SEQUENCE && !w)))
                 band->thr = FFMAX(PSY_3GPP_RPEMIN*band->thr, FFMIN(band->thr,

PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet));
@@ -436,6 +438,7 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
             psy_band->energy    = band->energy;
         }
     }
+
     memcpy(pch->prev_band, pch->band, sizeof(pch->band));
 }

-- 
1.7.4.1



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