diff options
Diffstat (limited to 'src/3rdparty/libwebp/src/dsp/filters.c')
| -rw-r--r-- | src/3rdparty/libwebp/src/dsp/filters.c | 39 |
1 files changed, 30 insertions, 9 deletions
diff --git a/src/3rdparty/libwebp/src/dsp/filters.c b/src/3rdparty/libwebp/src/dsp/filters.c index 5c30f2e..9f04faf 100644 --- a/src/3rdparty/libwebp/src/dsp/filters.c +++ b/src/3rdparty/libwebp/src/dsp/filters.c @@ -184,19 +184,40 @@ static void GradientFilter(const uint8_t* data, int width, int height, //------------------------------------------------------------------------------ -static void VerticalUnfilter(int width, int height, int stride, int row, - int num_rows, uint8_t* data) { - DoVerticalFilter(data, width, height, stride, row, num_rows, 1, data); +static void HorizontalUnfilter(const uint8_t* prev, const uint8_t* in, + uint8_t* out, int width) { + uint8_t pred = (prev == NULL) ? 0 : prev[0]; + int i; + for (i = 0; i < width; ++i) { + out[i] = pred + in[i]; + pred = out[i]; + } } -static void HorizontalUnfilter(int width, int height, int stride, int row, - int num_rows, uint8_t* data) { - DoHorizontalFilter(data, width, height, stride, row, num_rows, 1, data); +static void VerticalUnfilter(const uint8_t* prev, const uint8_t* in, + uint8_t* out, int width) { + if (prev == NULL) { + HorizontalUnfilter(NULL, in, out, width); + } else { + int i; + for (i = 0; i < width; ++i) out[i] = prev[i] + in[i]; + } } -static void GradientUnfilter(int width, int height, int stride, int row, - int num_rows, uint8_t* data) { - DoGradientFilter(data, width, height, stride, row, num_rows, 1, data); +static void GradientUnfilter(const uint8_t* prev, const uint8_t* in, + uint8_t* out, int width) { + if (prev == NULL) { + HorizontalUnfilter(NULL, in, out, width); + } else { + uint8_t top = prev[0], top_left = top, left = top; + int i; + for (i = 0; i < width; ++i) { + top = prev[i]; // need to read this first, in case prev==out + left = in[i] + GradientPredictor(left, top, top_left); + top_left = top; + out[i] = left; + } + } } //------------------------------------------------------------------------------ |