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Replace big square-root table by a call to ff_sqrt(). Based on a patch
by Reimar Döffinger. Originally committed as revision 20281 to svn://svn.ffmpeg.org/ffmpeg/trunk
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@ -29,7 +29,6 @@
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#define MAX_DPCM (127*127)
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static unsigned char dpcmValues[MAX_DPCM];
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typedef struct
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@ -37,18 +36,6 @@ typedef struct
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short lastSample[2];
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} ROQDPCMContext;
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static av_cold void roq_dpcm_table_init(void)
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{
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int i;
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/* Create a table of quick DPCM values */
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for (i=0; i<MAX_DPCM; i++) {
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int s= ff_sqrt(i);
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int mid= s*s + s;
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dpcmValues[i]= s + (i>mid);
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}
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}
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static av_cold int roq_dpcm_encode_init(AVCodecContext *avctx)
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{
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ROQDPCMContext *context = avctx->priv_data;
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@ -66,8 +53,6 @@ static av_cold int roq_dpcm_encode_init(AVCodecContext *avctx)
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return -1;
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}
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roq_dpcm_table_init();
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avctx->frame_size = ROQ_FIRST_FRAME_SIZE;
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context->lastSample[0] = context->lastSample[1] = 0;
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@ -92,8 +77,10 @@ static unsigned char dpcm_predict(short *previous, short current)
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if (diff >= MAX_DPCM)
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result = 127;
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else
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result = dpcmValues[diff];
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else {
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result = ff_sqrt(diff);
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result += diff > result*result+result;
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}
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/* See if this overflows */
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retry:
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