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authorshumkovnd <shumkovnd@yandex-team.com>2023-11-10 14:39:34 +0300
committershumkovnd <shumkovnd@yandex-team.com>2023-11-10 16:42:24 +0300
commit77eb2d3fdcec5c978c64e025ced2764c57c00285 (patch)
treec51edb0748ca8d4a08d7c7323312c27ba1a8b79a /contrib/libs/libwebp/enc/near_lossless_enc.c
parentdd6d20cadb65582270ac23f4b3b14ae189704b9d (diff)
downloadydb-77eb2d3fdcec5c978c64e025ced2764c57c00285.tar.gz
KIKIMR-19287: add task_stats_drawing script
Diffstat (limited to 'contrib/libs/libwebp/enc/near_lossless_enc.c')
-rw-r--r--contrib/libs/libwebp/enc/near_lossless_enc.c151
1 files changed, 151 insertions, 0 deletions
diff --git a/contrib/libs/libwebp/enc/near_lossless_enc.c b/contrib/libs/libwebp/enc/near_lossless_enc.c
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+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Near-lossless image preprocessing adjusts pixel values to help
+// compressibility with a guarantee of maximum deviation between original and
+// resulting pixel values.
+//
+// Author: Jyrki Alakuijala (jyrki@google.com)
+// Converted to C by Aleksander Kramarz (akramarz@google.com)
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "../dsp/lossless_common.h"
+#include "../utils/utils.h"
+#include "./vp8li_enc.h"
+
+#if (WEBP_NEAR_LOSSLESS == 1)
+
+#define MIN_DIM_FOR_NEAR_LOSSLESS 64
+#define MAX_LIMIT_BITS 5
+
+// Quantizes the value up or down to a multiple of 1<<bits (or to 255),
+// choosing the closer one, resolving ties using bankers' rounding.
+static uint32_t FindClosestDiscretized(uint32_t a, int bits) {
+ const uint32_t mask = (1u << bits) - 1;
+ const uint32_t biased = a + (mask >> 1) + ((a >> bits) & 1);
+ assert(bits > 0);
+ if (biased > 0xff) return 0xff;
+ return biased & ~mask;
+}
+
+// Applies FindClosestDiscretized to all channels of pixel.
+static uint32_t ClosestDiscretizedArgb(uint32_t a, int bits) {
+ return
+ (FindClosestDiscretized(a >> 24, bits) << 24) |
+ (FindClosestDiscretized((a >> 16) & 0xff, bits) << 16) |
+ (FindClosestDiscretized((a >> 8) & 0xff, bits) << 8) |
+ (FindClosestDiscretized(a & 0xff, bits));
+}
+
+// Checks if distance between corresponding channel values of pixels a and b
+// is within the given limit.
+static int IsNear(uint32_t a, uint32_t b, int limit) {
+ int k;
+ for (k = 0; k < 4; ++k) {
+ const int delta =
+ (int)((a >> (k * 8)) & 0xff) - (int)((b >> (k * 8)) & 0xff);
+ if (delta >= limit || delta <= -limit) {
+ return 0;
+ }
+ }
+ return 1;
+}
+
+static int IsSmooth(const uint32_t* const prev_row,
+ const uint32_t* const curr_row,
+ const uint32_t* const next_row,
+ int ix, int limit) {
+ // Check that all pixels in 4-connected neighborhood are smooth.
+ return (IsNear(curr_row[ix], curr_row[ix - 1], limit) &&
+ IsNear(curr_row[ix], curr_row[ix + 1], limit) &&
+ IsNear(curr_row[ix], prev_row[ix], limit) &&
+ IsNear(curr_row[ix], next_row[ix], limit));
+}
+
+// Adjusts pixel values of image with given maximum error.
+static void NearLossless(int xsize, int ysize, const uint32_t* argb_src,
+ int stride, int limit_bits, uint32_t* copy_buffer,
+ uint32_t* argb_dst) {
+ int x, y;
+ const int limit = 1 << limit_bits;
+ uint32_t* prev_row = copy_buffer;
+ uint32_t* curr_row = prev_row + xsize;
+ uint32_t* next_row = curr_row + xsize;
+ memcpy(curr_row, argb_src, xsize * sizeof(argb_src[0]));
+ memcpy(next_row, argb_src + stride, xsize * sizeof(argb_src[0]));
+
+ for (y = 0; y < ysize; ++y, argb_src += stride, argb_dst += xsize) {
+ if (y == 0 || y == ysize - 1) {
+ memcpy(argb_dst, argb_src, xsize * sizeof(argb_src[0]));
+ } else {
+ memcpy(next_row, argb_src + stride, xsize * sizeof(argb_src[0]));
+ argb_dst[0] = argb_src[0];
+ argb_dst[xsize - 1] = argb_src[xsize - 1];
+ for (x = 1; x < xsize - 1; ++x) {
+ if (IsSmooth(prev_row, curr_row, next_row, x, limit)) {
+ argb_dst[x] = curr_row[x];
+ } else {
+ argb_dst[x] = ClosestDiscretizedArgb(curr_row[x], limit_bits);
+ }
+ }
+ }
+ {
+ // Three-way swap.
+ uint32_t* const temp = prev_row;
+ prev_row = curr_row;
+ curr_row = next_row;
+ next_row = temp;
+ }
+ }
+}
+
+int VP8ApplyNearLossless(const WebPPicture* const picture, int quality,
+ uint32_t* const argb_dst) {
+ int i;
+ const int xsize = picture->width;
+ const int ysize = picture->height;
+ const int stride = picture->argb_stride;
+ uint32_t* const copy_buffer =
+ (uint32_t*)WebPSafeMalloc(xsize * 3, sizeof(*copy_buffer));
+ const int limit_bits = VP8LNearLosslessBits(quality);
+ assert(argb_dst != NULL);
+ assert(limit_bits > 0);
+ assert(limit_bits <= MAX_LIMIT_BITS);
+ if (copy_buffer == NULL) {
+ return 0;
+ }
+ // For small icon images, don't attempt to apply near-lossless compression.
+ if ((xsize < MIN_DIM_FOR_NEAR_LOSSLESS &&
+ ysize < MIN_DIM_FOR_NEAR_LOSSLESS) ||
+ ysize < 3) {
+ for (i = 0; i < ysize; ++i) {
+ memcpy(argb_dst + i * xsize, picture->argb + i * picture->argb_stride,
+ xsize * sizeof(*argb_dst));
+ }
+ WebPSafeFree(copy_buffer);
+ return 1;
+ }
+
+ NearLossless(xsize, ysize, picture->argb, stride, limit_bits, copy_buffer,
+ argb_dst);
+ for (i = limit_bits - 1; i != 0; --i) {
+ NearLossless(xsize, ysize, argb_dst, xsize, i, copy_buffer, argb_dst);
+ }
+ WebPSafeFree(copy_buffer);
+ return 1;
+}
+#else // (WEBP_NEAR_LOSSLESS == 1)
+
+// Define a stub to suppress compiler warnings.
+extern void VP8LNearLosslessStub(void);
+void VP8LNearLosslessStub(void) {}
+
+#endif // (WEBP_NEAR_LOSSLESS == 1)