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Viewing changes to gst-libs/ext/ffmpeg/libavutil/lfg.c

  • Committer: Bazaar Package Importer
  • Author(s): Sebastian Dröge
  • Date: 2010-02-19 18:14:59 UTC
  • mfrom: (4.1.5 experimental)
  • Revision ID: james.westby@ubuntu.com-20100219181459-mect96st3px2jfsi
Tags: 0.10.9.2-1
* New upstream pre-release:
  + debian/patches/03_restricted-caps.patch,
    debian/patches/04_ignore-vdpau.patch:
    - Dropped, merged upstream.
* debian/patches/03_too-new-codec-ids.patch:
  + Disable some ffmpeg codec IDs because Debian's
    ffmpeg is once again too old...

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Lines of Context:
gst-libs/ext/ffmpeg/libavutil/lfg.c
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    c->index=0;
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}
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void av_bmg_get(AVLFG *lfg, double out[2])
 
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{
 
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    double x1, x2, w;
 
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    do {
 
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        x1 = 2.0/UINT_MAX*av_lfg_get(lfg) - 1.0;
 
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        x2 = 2.0/UINT_MAX*av_lfg_get(lfg) - 1.0;
 
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        w = x1*x1 + x2*x2;
 
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    } while (w >= 1.0);
 
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    w = sqrt((-2.0 * log(w)) / w);
 
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    out[0] = x1 * w;
 
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    out[1] = x2 * w;
 
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}
 
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#ifdef TEST
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#include "log.h"
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#include "common.h"
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//            av_log(NULL,AV_LOG_ERROR, "%X\n", av_lfg_get(&state));
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            x+=av_lfg_get(&state);
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        }
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        STOP_TIMER("624 calls of av_random");
 
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        STOP_TIMER("624 calls of av_lfg_get");
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    }
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    av_log(NULL, AV_LOG_ERROR, "final value:%X\n", x);
 
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    /* BMG usage example */
 
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    {
 
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        double mean   = 1000;
 
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        double stddev = 53;
 
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        av_lfg_init(&state, 42);
 
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        for (i = 0; i < 1000; i += 2) {
 
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            double bmg_out[2];
 
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            av_bmg_get(&state, bmg_out);
 
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            av_log(NULL, AV_LOG_INFO,
 
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                   "%f\n%f\n",
 
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                   bmg_out[0] * stddev + mean,
 
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                   bmg_out[1] * stddev + mean);
 
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        }
 
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    }
 
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    return 0;
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}
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#endif