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

78 lines
1.6 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;
}
/*
* Squash arrays.
* For instance:
* 2.1:
*
* | FL | FR | LFE | emp | emp | emp |emp |emp |
* | | |
* | FL | FR | LFE |
*/
int repack_squash(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;
/* Audio needs squashing in order to avoid resampling issues.
*/
while (src != esrc) {
__m128i target = _mm_load_si128(src++);
_mm_storeu_si128((__m128i *)dst, target);
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;
repack->base_src_size = 8 * (16 / 8);
repack->base_dst_size = (int)repack_mode * (16 / 8);
repack->extra_dst_size = 8 - (int)repack_mode;
repack->repack_func = &repack_squash;
return 0;
}
void audio_repack_free(struct audio_repack *repack)
{
if (repack->packet_buffer)
bfree(repack->packet_buffer);
memset(repack, 0, sizeof(*repack));
}