[FFmpeg-cvslog] swscale/input: clip rgbf32 values before lrintf

[Mark Reid]

ffmpeg | branch: master | Mark Reid <mindmark at gmail.com> | Sun Nov 14 22:22:21 2021 -0800| [3f4ce004b8afa915499c367e78ae080bc457624c] | committer: James Almer

swscale/input: clip rgbf32 values before lrintf

if the float pixel * 65535.0f > 2147483647.0f
lrintf may overfow and return negative values, depending on implementation.
nan and +/-inf values may also be implementation defined

clip the value first so lrintf always works.

values <     0.0f, -inf, nan = 0.0f
values > 65535.0f, +inf      = 65535.0f

old timings
 195960 decicycles in planar_rgbf32le_to_uv,       1 runs,      0 skips
 186120 decicycles in planar_rgbf32le_to_uv,       2 runs,      0 skips
 188645 decicycles in planar_rgbf32le_to_uv,       4 runs,      0 skips
 183625 decicycles in planar_rgbf32le_to_uv,       8 runs,      0 skips
 181157 decicycles in planar_rgbf32le_to_uv,      16 runs,      0 skips
 177533 decicycles in planar_rgbf32le_to_uv,      32 runs,      0 skips
 175689 decicycles in planar_rgbf32le_to_uv,      64 runs,      0 skips

 232960 decicycles in planar_rgbf32be_to_uv,       1 runs,      0 skips
 221380 decicycles in planar_rgbf32be_to_uv,       2 runs,      0 skips
 216640 decicycles in planar_rgbf32be_to_uv,       4 runs,      0 skips
 213505 decicycles in planar_rgbf32be_to_uv,       8 runs,      0 skips
 211558 decicycles in planar_rgbf32be_to_uv,      16 runs,      0 skips
 210596 decicycles in planar_rgbf32be_to_uv,      32 runs,      0 skips
 210202 decicycles in planar_rgbf32be_to_uv,      64 runs,      0 skips

 161680 decicycles in planar_rgbf32le_to_y,       1 runs,      0 skips
 153540 decicycles in planar_rgbf32le_to_y,       2 runs,      0 skips
 148255 decicycles in planar_rgbf32le_to_y,       4 runs,      0 skips
 140600 decicycles in planar_rgbf32le_to_y,       8 runs,      0 skips
 132935 decicycles in planar_rgbf32le_to_y,      16 runs,      0 skips
 128531 decicycles in planar_rgbf32le_to_y,      32 runs,      0 skips
 140933 decicycles in planar_rgbf32le_to_y,      64 runs,      0 skips

 190980 decicycles in planar_rgbf32be_to_y,       1 runs,      0 skips
 176080 decicycles in planar_rgbf32be_to_y,       2 runs,      0 skips
 167980 decicycles in planar_rgbf32be_to_y,       4 runs,      0 skips
 164685 decicycles in planar_rgbf32be_to_y,       8 runs,      0 skips
 162751 decicycles in planar_rgbf32be_to_y,      16 runs,      0 skips
 162404 decicycles in planar_rgbf32be_to_y,      32 runs,      0 skips
 167849 decicycles in planar_rgbf32be_to_y,      64 runs,      0 skips

new timings
 183320 decicycles in planar_rgbf32le_to_uv,       1 runs,      0 skips
 175700 decicycles in planar_rgbf32le_to_uv,       2 runs,      0 skips
 179570 decicycles in planar_rgbf32le_to_uv,       4 runs,      0 skips
 172932 decicycles in planar_rgbf32le_to_uv,       8 runs,      0 skips
 168707 decicycles in planar_rgbf32le_to_uv,      16 runs,      0 skips
 165224 decicycles in planar_rgbf32le_to_uv,      32 runs,      0 skips
 163423 decicycles in planar_rgbf32le_to_uv,      64 runs,      0 skips

 184940 decicycles in planar_rgbf32be_to_uv,       1 runs,      0 skips
 185150 decicycles in planar_rgbf32be_to_uv,       2 runs,      0 skips
 185790 decicycles in planar_rgbf32be_to_uv,       4 runs,      0 skips
 185472 decicycles in planar_rgbf32be_to_uv,       8 runs,      0 skips
 185277 decicycles in planar_rgbf32be_to_uv,      16 runs,      0 skips
 185813 decicycles in planar_rgbf32be_to_uv,      32 runs,      0 skips
 185332 decicycles in planar_rgbf32be_to_uv,      64 runs,      0 skips

 145400 decicycles in planar_rgbf32le_to_y,       1 runs,      0 skips
 145100 decicycles in planar_rgbf32le_to_y,       2 runs,      0 skips
 143490 decicycles in planar_rgbf32le_to_y,       4 runs,      0 skips
 136687 decicycles in planar_rgbf32le_to_y,       8 runs,      0 skips
 131271 decicycles in planar_rgbf32le_to_y,      16 runs,      0 skips
 128698 decicycles in planar_rgbf32le_to_y,      32 runs,      0 skips
 127170 decicycles in planar_rgbf32le_to_y,      64 runs,      0 skips

 156020 decicycles in planar_rgbf32be_to_y,       1 runs,      0 skips
 146990 decicycles in planar_rgbf32be_to_y,       2 runs,      0 skips
 142020 decicycles in planar_rgbf32be_to_y,       4 runs,      0 skips
 141052 decicycles in planar_rgbf32be_to_y,       8 runs,      0 skips
 138973 decicycles in planar_rgbf32be_to_y,      16 runs,      0 skips
 138027 decicycles in planar_rgbf32be_to_y,      32 runs,      0 skips
 143939 decicycles in planar_rgbf32be_to_y,      64 runs,      0 skips

Reviewed-by: Michael Niedermayer <michael at niedermayer.cc>
Signed-off-by: James Almer <jamrial at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3f4ce004b8afa915499c367e78ae080bc457624c
---

 libswscale/input.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/libswscale/input.c b/libswscale/input.c
index 90efdd2ffc..1351ea5bd4 100644
--- a/libswscale/input.c
+++ b/libswscale/input.c
@@ -973,7 +973,7 @@ static av_always_inline void planar_rgbf32_to_a(uint8_t *_dst, const uint8_t *_s
     uint16_t *dst        = (uint16_t *)_dst;
 
     for (i = 0; i < width; i++) {
-        dst[i] = av_clip_uint16(lrintf(65535.0f * rdpx(src[3] + i)));
+        dst[i] = lrintf(av_clipf(65535.0f * rdpx(src[3] + i), 0.0f, 65535.0f));
     }
 }
 
@@ -987,9 +987,9 @@ static av_always_inline void planar_rgbf32_to_uv(uint8_t *_dstU, uint8_t *_dstV,
     int32_t rv = rgb2yuv[RV_IDX], gv = rgb2yuv[GV_IDX], bv = rgb2yuv[BV_IDX];
 
     for (i = 0; i < width; i++) {
-        int g = av_clip_uint16(lrintf(65535.0f * rdpx(src[0] + i)));
-        int b = av_clip_uint16(lrintf(65535.0f * rdpx(src[1] + i)));
-        int r = av_clip_uint16(lrintf(65535.0f * rdpx(src[2] + i)));
+        int g = lrintf(av_clipf(65535.0f * rdpx(src[0] + i), 0.0f, 65535.0f));
+        int b = lrintf(av_clipf(65535.0f * rdpx(src[1] + i), 0.0f, 65535.0f));
+        int r = lrintf(av_clipf(65535.0f * rdpx(src[2] + i), 0.0f, 65535.0f));
 
         dstU[i] = (ru*r + gu*g + bu*b + (0x10001 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT;
         dstV[i] = (rv*r + gv*g + bv*b + (0x10001 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT;
@@ -1005,9 +1005,9 @@ static av_always_inline void planar_rgbf32_to_y(uint8_t *_dst, const uint8_t *_s
     int32_t ry = rgb2yuv[RY_IDX], gy = rgb2yuv[GY_IDX], by = rgb2yuv[BY_IDX];
 
     for (i = 0; i < width; i++) {
-        int g = av_clip_uint16(lrintf(65535.0f * rdpx(src[0] + i)));
-        int b = av_clip_uint16(lrintf(65535.0f * rdpx(src[1] + i)));
-        int r = av_clip_uint16(lrintf(65535.0f * rdpx(src[2] + i)));
+        int g = lrintf(av_clipf(65535.0f * rdpx(src[0] + i), 0.0f, 65535.0f));
+        int b = lrintf(av_clipf(65535.0f * rdpx(src[1] + i), 0.0f, 65535.0f));
+        int r = lrintf(av_clipf(65535.0f * rdpx(src[2] + i), 0.0f, 65535.0f));
 
         dst[i] = (ry*r + gy*g + by*b + (0x2001 << (RGB2YUV_SHIFT - 1))) >> RGB2YUV_SHIFT;
     }
@@ -1021,7 +1021,7 @@ static av_always_inline void grayf32ToY16_c(uint8_t *_dst, const uint8_t *_src,
     uint16_t *dst    = (uint16_t *)_dst;
 
     for (i = 0; i < width; ++i){
-        dst[i] = av_clip_uint16(lrintf(65535.0f * rdpx(src + i)));
+        dst[i] = lrintf(av_clipf(65535.0f * rdpx(src + i), 0.0f,  65535.0f));
     }
 }