On Sunday 01 March 2015 11:22:10 am Michael Niedermayer wrote:
> On Sun, Mar 01, 2015 at 09:44:30AM +0100, Carl Eugen Hoyos wrote:
> > Attached untested patch should fix compilation on broken platforms.
> > We don't use round() currently because it appears less portable than
> > lrintf().
> yes reducing float code usage should be fine, less potential to
> cause problems with regression tests
New patch attached.
Please review, Carl Eugen
diff --git a/libavcodec/pngenc.c b/libavcodec/pngenc.c
index 9fd8eef..b6eedde 100644
--- a/libavcodec/pngenc.c
+++ b/libavcodec/pngenc.c
@@ -231,78 +231,77 @@ static int png_write_row(PNGEncContext *s, const uint8_t
*data, int size)
return 0;
}
-#define AV_WB32_PNG(buf, n) (AV_WB32(buf, round((n) * 100000)))
static int png_get_chrm(enum AVColorPrimaries prim, uint8_t *buf)
{
- double rx, ry, gx, gy, bx, by, wx = 0.3127, wy = 0.3290;
+ int rx, ry, gx, gy, bx, by, wx = 312700, wy = 329000;
switch (prim) {
case AVCOL_PRI_BT709:
- rx = 0.640; ry = 0.330;
- gx = 0.300; gy = 0.600;
- bx = 0.150; by = 0.060;
+ rx = 64000; ry = 33000;
+ gx = 30000; gy = 60000;
+ bx = 15000; by = 6000;
break;
case AVCOL_PRI_BT470M:
- rx = 0.670; ry = 0.330;
- gx = 0.210; gy = 0.710;
- bx = 0.140; by = 0.080;
- wx = 0.310; wy = 0.316;
+ rx = 67000; ry = 33000;
+ gx = 21000; gy = 71000;
+ bx = 14000; by = 8000;
+ wx = 31000; wy = 31600;
break;
case AVCOL_PRI_BT470BG:
- rx = 0.640; ry = 0.330;
- gx = 0.290; gy = 0.600;
- bx = 0.150; by = 0.060;
+ rx = 64000; ry = 33000;
+ gx = 29000; gy = 60000;
+ bx = 15000; by = 06000;
break;
case AVCOL_PRI_SMPTE170M:
case AVCOL_PRI_SMPTE240M:
- rx = 0.630; ry = 0.340;
- gx = 0.310; gy = 0.595;
- bx = 0.155; by = 0.070;
+ rx = 63000; ry = 34000;
+ gx = 31000; gy = 59500;
+ bx = 15500; by = 7000;
break;
case AVCOL_PRI_BT2020:
- rx = 0.708; ry = 0.292;
- gx = 0.170; gy = 0.797;
- bx = 0.131; by = 0.046;
+ rx = 70800; ry = 29200;
+ gx = 17000; gy = 79700;
+ bx = 13100; by = 4600;
break;
default:
return 0;
}
- AV_WB32_PNG(buf , wx); AV_WB32_PNG(buf + 4 , wy);
- AV_WB32_PNG(buf + 8 , rx); AV_WB32_PNG(buf + 12, ry);
- AV_WB32_PNG(buf + 16, gx); AV_WB32_PNG(buf + 20, gy);
- AV_WB32_PNG(buf + 24, bx); AV_WB32_PNG(buf + 28, by);
+ AV_WB32(buf , wx); AV_WB32(buf + 4 , wy);
+ AV_WB32(buf + 8 , rx); AV_WB32(buf + 12, ry);
+ AV_WB32(buf + 16, gx); AV_WB32(buf + 20, gy);
+ AV_WB32(buf + 24, bx); AV_WB32(buf + 28, by);
return 1;
}
static int png_get_gama(enum AVColorTransferCharacteristic trc, uint8_t *buf)
{
- double gamma;
+ int gamma;
switch (trc) {
case AVCOL_TRC_BT709:
case AVCOL_TRC_SMPTE170M:
case AVCOL_TRC_SMPTE240M:
case AVCOL_TRC_BT1361_ECG:
case AVCOL_TRC_BT2020_10:
case AVCOL_TRC_BT2020_12:
/* these share a segmented TRC, but gamma 1.961 is a close
approximation, and also more correct for decoding content */
- gamma = 1.961;
+ gamma = 50994; // 100000 / 1.961
break;
case AVCOL_TRC_GAMMA22:
case AVCOL_TRC_IEC61966_2_1:
- gamma = 2.2;
+ gamma = 45455; // 100000 / 2.2
break;
case AVCOL_TRC_GAMMA28:
- gamma = 2.8;
+ gamma = 35714; // 100000 / 2.8
break;
case AVCOL_TRC_LINEAR:
- gamma = 1.0;
+ gamma = 100000;
break;
default:
return 0;
}
- AV_WB32_PNG(buf, 1.0 / gamma);
+ AV_WB32(buf, gamma);
return 1;
}
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