mirror of https://git.ffmpeg.org/ffmpeg.git
Split out initialization of MDCT tables into a separate function.
Originally committed as revision 25954 to svn://svn.ffmpeg.org/ffmpeg/trunk
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0796546370
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a8d2b06b7c
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@ -115,6 +115,22 @@ static av_cold void fft_init(int ln)
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}
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}
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}
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}
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static av_cold void mdct_init(int nbits)
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{
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int i;
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float alpha;
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int n = 1 << nbits;
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int n4 = n >> 2;
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fft_init(nbits - 2);
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for(i=0;i<n4;i++) {
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alpha = 2 * M_PI * (i + 1.0 / 8.0) / n;
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xcos1[i] = fix15(-cos(alpha));
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xsin1[i] = fix15(-sin(alpha));
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}
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}
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/* butter fly op */
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/* butter fly op */
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#define BF(pre, pim, qre, qim, pre1, pim1, qre1, qim1) \
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#define BF(pre, pim, qre, qim, pre1, pim1, qre1, qim1) \
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{\
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{\
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@ -637,7 +653,6 @@ static av_cold int AC3_encode_init(AVCodecContext *avctx)
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int bitrate = avctx->bit_rate;
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int bitrate = avctx->bit_rate;
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AC3EncodeContext *s = avctx->priv_data;
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AC3EncodeContext *s = avctx->priv_data;
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int i, j, ch;
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int i, j, ch;
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float alpha;
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int bw_code;
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int bw_code;
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avctx->frame_size = AC3_FRAME_SIZE;
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avctx->frame_size = AC3_FRAME_SIZE;
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@ -705,13 +720,7 @@ static av_cold int AC3_encode_init(AVCodecContext *avctx)
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/* initial snr offset */
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/* initial snr offset */
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s->coarse_snr_offset = 40;
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s->coarse_snr_offset = 40;
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/* mdct init */
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mdct_init(9);
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fft_init(MDCT_NBITS - 2);
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for(i=0;i<MDCT_SAMPLES/4;i++) {
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alpha = 2 * M_PI * (i + 1.0 / 8.0) / (float)MDCT_SAMPLES;
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xcos1[i] = fix15(-cos(alpha));
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xsin1[i] = fix15(-sin(alpha));
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}
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avctx->coded_frame= avcodec_alloc_frame();
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avctx->coded_frame= avcodec_alloc_frame();
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avctx->coded_frame->key_frame= 1;
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avctx->coded_frame->key_frame= 1;
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