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atrac3: separate window initialization from IMDCT initialization

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This commit is contained in:
Justin Ruggles 2012-10-18 22:56:10 -04:00
parent c51311b907
commit 78edce3f19
1 changed files with 9 additions and 12 deletions
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21
libavcodec/atrac3.c
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@ -174,7 +174,7 @@ static int decode_bytes(const uint8_t *input, uint8_t *out, int bytes)
return off;
}
static av_cold int init_atrac3_transforms(ATRAC3Context *q)
static av_cold void init_atrac3_window(void)
{
float enc_window[256];
int i;
@ -184,17 +184,12 @@ static av_cold int init_atrac3_transforms(ATRAC3Context *q)
for (i = 0; i < 256; i++)
enc_window[i] = (sin(((i + 0.5) / 256.0 - 0.5) * M_PI) + 1.0) * 0.5;
if (!mdct_window[0]) {
for (i = 0; i < 256; i++) {
mdct_window[i] = enc_window[i] /
(enc_window[ i] * enc_window[ i] +
enc_window[255 - i] * enc_window[255 - i]);
mdct_window[511 - i] = mdct_window[i];
}
for (i = 0; i < 256; i++) {
mdct_window[i] = enc_window[i] /
(enc_window[ i] * enc_window[ i] +
enc_window[255 - i] * enc_window[255 - i]);
mdct_window[511 - i] = mdct_window[i];
}
/* initialize the MDCT transform */
return ff_mdct_init(&q->mdct_ctx, 9, 1, 1.0 / 32768);
}
static av_cold int atrac3_decode_close(AVCodecContext *avctx)
@ -956,12 +951,14 @@ static av_cold int atrac3_decode_init(AVCodecContext *avctx)
avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
if ((ret = init_atrac3_transforms(q))) {
/* initialize the MDCT transform */
if ((ret = ff_mdct_init(&q->mdct_ctx, 9, 1, 1.0 / 32768)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error initializing MDCT\n");
av_freep(&q->decoded_bytes_buffer);
return ret;
}
init_atrac3_window();
ff_atrac_generate_tables();
/* Generate gain tables */