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-rw-r--r--src/3rdparty/libwebp/src/utils/filters.c204
1 files changed, 7 insertions, 197 deletions
diff --git a/src/3rdparty/libwebp/src/utils/filters.c b/src/3rdparty/libwebp/src/utils/filters.c
index 2d15bd0..15543b1 100644
--- a/src/3rdparty/libwebp/src/utils/filters.c
+++ b/src/3rdparty/libwebp/src/utils/filters.c
@@ -7,200 +7,27 @@
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
-// Spatial prediction using various filters
+// filter estimation
//
// Author: Urvang (urvang@google.com)
#include "./filters.h"
-#include <assert.h>
#include <stdlib.h>
#include <string.h>
-//------------------------------------------------------------------------------
-// Helpful macro.
-
-# define SANITY_CHECK(in, out) \
- assert(in != NULL); \
- assert(out != NULL); \
- assert(width > 0); \
- assert(height > 0); \
- assert(stride >= width); \
- assert(row >= 0 && num_rows > 0 && row + num_rows <= height); \
- (void)height; // Silence unused warning.
-
-static WEBP_INLINE void PredictLine(const uint8_t* src, const uint8_t* pred,
- uint8_t* dst, int length, int inverse) {
- int i;
- if (inverse) {
- for (i = 0; i < length; ++i) dst[i] = src[i] + pred[i];
- } else {
- for (i = 0; i < length; ++i) dst[i] = src[i] - pred[i];
- }
-}
-
-//------------------------------------------------------------------------------
-// Horizontal filter.
-
-static WEBP_INLINE void DoHorizontalFilter(const uint8_t* in,
- int width, int height, int stride,
- int row, int num_rows,
- int inverse, uint8_t* out) {
- const uint8_t* preds;
- const size_t start_offset = row * stride;
- const int last_row = row + num_rows;
- SANITY_CHECK(in, out);
- in += start_offset;
- out += start_offset;
- preds = inverse ? out : in;
-
- if (row == 0) {
- // Leftmost pixel is the same as input for topmost scanline.
- out[0] = in[0];
- PredictLine(in + 1, preds, out + 1, width - 1, inverse);
- row = 1;
- preds += stride;
- in += stride;
- out += stride;
- }
-
- // Filter line-by-line.
- while (row < last_row) {
- // Leftmost pixel is predicted from above.
- PredictLine(in, preds - stride, out, 1, inverse);
- PredictLine(in + 1, preds, out + 1, width - 1, inverse);
- ++row;
- preds += stride;
- in += stride;
- out += stride;
- }
-}
-
-static void HorizontalFilter(const uint8_t* data, int width, int height,
- int stride, uint8_t* filtered_data) {
- DoHorizontalFilter(data, width, height, stride, 0, height, 0, filtered_data);
-}
-
-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);
-}
-
-//------------------------------------------------------------------------------
-// Vertical filter.
-
-static WEBP_INLINE void DoVerticalFilter(const uint8_t* in,
- int width, int height, int stride,
- int row, int num_rows,
- int inverse, uint8_t* out) {
- const uint8_t* preds;
- const size_t start_offset = row * stride;
- const int last_row = row + num_rows;
- SANITY_CHECK(in, out);
- in += start_offset;
- out += start_offset;
- preds = inverse ? out : in;
-
- if (row == 0) {
- // Very first top-left pixel is copied.
- out[0] = in[0];
- // Rest of top scan-line is left-predicted.
- PredictLine(in + 1, preds, out + 1, width - 1, inverse);
- row = 1;
- in += stride;
- out += stride;
- } else {
- // We are starting from in-between. Make sure 'preds' points to prev row.
- preds -= stride;
- }
-
- // Filter line-by-line.
- while (row < last_row) {
- PredictLine(in, preds, out, width, inverse);
- ++row;
- preds += stride;
- in += stride;
- out += stride;
- }
-}
-
-static void VerticalFilter(const uint8_t* data, int width, int height,
- int stride, uint8_t* filtered_data) {
- DoVerticalFilter(data, width, height, stride, 0, height, 0, filtered_data);
-}
-
-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);
-}
+// -----------------------------------------------------------------------------
+// Quick estimate of a potentially interesting filter mode to try.
-//------------------------------------------------------------------------------
-// Gradient filter.
+#define SMAX 16
+#define SDIFF(a, b) (abs((a) - (b)) >> 4) // Scoring diff, in [0..SMAX)
static WEBP_INLINE int GradientPredictor(uint8_t a, uint8_t b, uint8_t c) {
const int g = a + b - c;
return ((g & ~0xff) == 0) ? g : (g < 0) ? 0 : 255; // clip to 8bit
}
-static WEBP_INLINE void DoGradientFilter(const uint8_t* in,
- int width, int height, int stride,
- int row, int num_rows,
- int inverse, uint8_t* out) {
- const uint8_t* preds;
- const size_t start_offset = row * stride;
- const int last_row = row + num_rows;
- SANITY_CHECK(in, out);
- in += start_offset;
- out += start_offset;
- preds = inverse ? out : in;
-
- // left prediction for top scan-line
- if (row == 0) {
- out[0] = in[0];
- PredictLine(in + 1, preds, out + 1, width - 1, inverse);
- row = 1;
- preds += stride;
- in += stride;
- out += stride;
- }
-
- // Filter line-by-line.
- while (row < last_row) {
- int w;
- // leftmost pixel: predict from above.
- PredictLine(in, preds - stride, out, 1, inverse);
- for (w = 1; w < width; ++w) {
- const int pred = GradientPredictor(preds[w - 1],
- preds[w - stride],
- preds[w - stride - 1]);
- out[w] = in[w] + (inverse ? pred : -pred);
- }
- ++row;
- preds += stride;
- in += stride;
- out += stride;
- }
-}
-
-static void GradientFilter(const uint8_t* data, int width, int height,
- int stride, uint8_t* filtered_data) {
- DoGradientFilter(data, width, height, stride, 0, height, 0, filtered_data);
-}
-
-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);
-}
-
-#undef SANITY_CHECK
-
-// -----------------------------------------------------------------------------
-// Quick estimate of a potentially interesting filter mode to try.
-
-#define SMAX 16
-#define SDIFF(a, b) (abs((a) - (b)) >> 4) // Scoring diff, in [0..SMAX)
-
-WEBP_FILTER_TYPE EstimateBestFilter(const uint8_t* data,
- int width, int height, int stride) {
+WEBP_FILTER_TYPE WebPEstimateBestFilter(const uint8_t* data,
+ int width, int height, int stride) {
int i, j;
int bins[WEBP_FILTER_LAST][SMAX];
memset(bins, 0, sizeof(bins));
@@ -247,20 +74,3 @@ WEBP_FILTER_TYPE EstimateBestFilter(const uint8_t* data,
#undef SDIFF
//------------------------------------------------------------------------------
-
-const WebPFilterFunc WebPFilters[WEBP_FILTER_LAST] = {
- NULL, // WEBP_FILTER_NONE
- HorizontalFilter, // WEBP_FILTER_HORIZONTAL
- VerticalFilter, // WEBP_FILTER_VERTICAL
- GradientFilter // WEBP_FILTER_GRADIENT
-};
-
-const WebPUnfilterFunc WebPUnfilters[WEBP_FILTER_LAST] = {
- NULL, // WEBP_FILTER_NONE
- HorizontalUnfilter, // WEBP_FILTER_HORIZONTAL
- VerticalUnfilter, // WEBP_FILTER_VERTICAL
- GradientUnfilter // WEBP_FILTER_GRADIENT
-};
-
-//------------------------------------------------------------------------------
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-21 03:29:31 +0000