When sbr->reset is set in encode_frame, a bunch of qsort calls might get made.
Thus, there is the potential of calling qsort whenever the spectral
contents change.
AV_QSORT is substantially faster due to the inlining of the comparison callback.
Thus, the increase in performance should be worth the increase in binary size.
Tested with FATE.
Signed-off-by: Ganesh Ajjanagadde <gajjanaga...@gmail.com>
--------------------------------------------------------------------------------
Please note that I am not not knowledgable about AAC, and above analysis
was based on a quick glance at the code. I could not get benchmarks with
runs > 1 easily (even with stream_loop), hence they are omitted.
Furthermore, it seems like AAC is under active work, so I defer
meaningful benchmarks to the maintainers.
---
libavcodec/aacsbr_template.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/libavcodec/aacsbr_template.c b/libavcodec/aacsbr_template.c
index d31b71e..9561ba0 100644
--- a/libavcodec/aacsbr_template.c
+++ b/libavcodec/aacsbr_template.c
@@ -32,6 +32,8 @@
* @author Zoran Basaric ( zoran.basa...@imgtec.com )
*/
+#include "libavutil/qsort.h"
+
av_cold void AAC_RENAME(ff_aac_sbr_init)(void)
{
static const struct {
@@ -138,8 +140,8 @@ static void sbr_make_f_tablelim(SpectralBandReplication
*sbr)
memcpy(sbr->f_tablelim + sbr->n[0] + 1, patch_borders + 1,
(sbr->num_patches - 1) * sizeof(patch_borders[0]));
- qsort(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
- sizeof(sbr->f_tablelim[0]),
+ AV_QSORT(sbr->f_tablelim, sbr->num_patches + sbr->n[0],
+ uint16_t,
qsort_comparison_function_int16);
sbr->n_lim = sbr->n[0] + sbr->num_patches - 1;
@@ -296,7 +298,7 @@ static int sbr_make_f_master(AACContext *ac,
SpectralBandReplication *sbr,
if (spectrum->bs_stop_freq < 14) {
sbr->k[2] = stop_min;
make_bands(stop_dk, stop_min, 64, 13);
- qsort(stop_dk, 13, sizeof(stop_dk[0]),
qsort_comparison_function_int16);
+ AV_QSORT(stop_dk, 13, int16_t, qsort_comparison_function_int16);
for (k = 0; k < spectrum->bs_stop_freq; k++)
sbr->k[2] += stop_dk[k];
} else if (spectrum->bs_stop_freq == 14) {
@@ -389,7 +391,7 @@ static int sbr_make_f_master(AACContext *ac,
SpectralBandReplication *sbr,
make_bands(vk0+1, sbr->k[0], sbr->k[1], num_bands_0);
- qsort(vk0 + 1, num_bands_0, sizeof(vk0[1]),
qsort_comparison_function_int16);
+ AV_QSORT(vk0 + 1, num_bands_0, int16_t,
qsort_comparison_function_int16);
vdk0_max = vk0[num_bands_0];
vk0[0] = sbr->k[0];
@@ -430,13 +432,13 @@ static int sbr_make_f_master(AACContext *ac,
SpectralBandReplication *sbr,
if (vdk1_min < vdk0_max) {
int change;
- qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]),
qsort_comparison_function_int16);
+ AV_QSORT(vk1 + 1, num_bands_1, int16_t,
qsort_comparison_function_int16);
change = FFMIN(vdk0_max - vk1[1], (vk1[num_bands_1] - vk1[1])
>> 1);
vk1[1] += change;
vk1[num_bands_1] -= change;
}
- qsort(vk1 + 1, num_bands_1, sizeof(vk1[1]),
qsort_comparison_function_int16);
+ AV_QSORT(vk1 + 1, num_bands_1, int16_t,
qsort_comparison_function_int16);
vk1[0] = sbr->k[1];
for (k = 1; k <= num_bands_1; k++) {
--
2.6.2
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