obs-studio/plugins/decklink/audio-repack.c

143 lines
3.3 KiB
C

#include "audio-repack.h"
#include <emmintrin.h>
int check_buffer(struct audio_repack *repack,
uint32_t frame_count)
{
const uint32_t new_size = frame_count * repack->base_dst_size
+ repack->extra_dst_size;
if (repack->packet_size < new_size) {
repack->packet_buffer = brealloc(
repack->packet_buffer, new_size);
if (!repack->packet_buffer)
return -1;
repack->packet_size = new_size;
}
return 0;
}
/*
* Swap channel 3 & 4, 5 & 7, 6 & 8 and squash arrays
* 2.1:
*
* | FL | FR | LFE | emp | emp | emp |emp |emp |
* | | |
* | FL | FR | LFE |
* 4.0 (quad):
*
* | FL | FR | BR | BL | emp | emp |emp |emp |
* | | x |
* | FL | FR | BL | BC |
*
* 4.1:
*
* | FL | FR |LFE | FC | BC | emp |emp |emp |
* | | x | |
* | FL | FR | FC |LFE | BC |
*
* 5.1:
*
* | FL | FR |LFE | FC |(emp|emp)|(BL|BR)|
* | | x x
* | FL | FR | FC |LFE | BL | BR |
*
* 7.1:
*
* | FL | FR |LFE | FC |( SL | SR )|(BL |BR )|
* | | x X
* | FL | FR | FC |LFE |( BL | BR )|(SL |SR )|
*/
int repack_squash_swap(struct audio_repack *repack,
const uint8_t *bsrc, uint32_t frame_count)
{
if (check_buffer(repack, frame_count) < 0)
return -1;
int squash = repack->extra_dst_size;
const __m128i *src = (__m128i *)bsrc;
const __m128i *esrc = src + frame_count;
uint16_t *dst = (uint16_t *)repack->packet_buffer;
/* 2.1 audio does not require re-ordering but still needs squashing
* in order to avoid sampling issues.
*/
if (squash == 5) {
while (src != esrc) {
__m128i target = _mm_load_si128(src++);
_mm_storeu_si128((__m128i *)dst, target);
dst += 8 - squash;
}
} else {
while (src != esrc) {
__m128i target = _mm_load_si128(src++);
__m128i buf = _mm_shufflelo_epi16(target, _MM_SHUFFLE(2, 3, 1, 0));
__m128i buf2 = _mm_shufflehi_epi16(buf, _MM_SHUFFLE(1, 0, 3, 2));
_mm_storeu_si128((__m128i *)dst, buf2);
dst += 8 - squash;
}
}
return 0;
}
int audio_repack_init(struct audio_repack *repack,
audio_repack_mode_t repack_mode, uint8_t sample_bit)
{
memset(repack, 0, sizeof(*repack));
if (sample_bit != 16)
return -1;
switch (repack_mode) {
case repack_mode_8to3ch_swap23:
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = 3 * (16 / 8);
repack->extra_dst_size = 5;
repack->repack_func = &repack_squash_swap;
break;
case repack_mode_8to4ch_swap23:
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = 4 * (16 / 8);
repack->extra_dst_size = 4;
repack->repack_func = &repack_squash_swap;
break;
case repack_mode_8to5ch_swap23:
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = 5 * (16 / 8);
repack->extra_dst_size = 3;
repack->repack_func = &repack_squash_swap;
break;
case repack_mode_8to6ch_swap23:
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = 6 * (16 / 8);
repack->extra_dst_size = 2;
repack->repack_func = &repack_squash_swap;
break;
case repack_mode_8ch_swap23_swap46_swap57:
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = 8 * (16 / 8);
repack->extra_dst_size = 0;
repack->repack_func = &repack_squash_swap;
break;
default: return -1;
}
return 0;
}
void audio_repack_free(struct audio_repack *repack)
{
if (repack->packet_buffer)
bfree(repack->packet_buffer);
memset(repack, 0, sizeof(*repack));
}