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diff --git a/Build/source/libs/gd/libgd-2.1.0/src/webpimg.c b/Build/source/libs/gd/libgd-2.1.0/src/webpimg.c
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+++ b/Build/source/libs/gd/libgd-2.1.0/src/webpimg.c
@@ -0,0 +1,905 @@
+/*===========================================================================*
+ - Copyright 2010 Google Inc.
+ -
+ - This code is licensed under the same terms as WebM:
+ - Software License Agreement: http://www.webmproject.org/license/software/
+ - Additional IP Rights Grant: http://www.webmproject.org/license/additional/
+ *===========================================================================*/
+
+/*
+ * Encoding/Decoding of WebP still image compression format.
+ *
+ * 1. WebPDecode: Takes an array of bytes (string) corresponding to the WebP
+ * encoded image and generates output in the YUV format with
+ * the color components U, V subsampled to 1/2 resolution along
+ * each dimension.
+ *
+ * 2. YUV420toRGBA: Converts from YUV (with color subsampling) such as produced
+ * by the WebPDecode routine into 32 bits per pixel RGBA data
+ * array. This data array can be directly used by the Leptonica
+ * Pix in-memory image format.
+ *
+ * 3. WebPEncode: Takes a Y, U, V data buffers (with color components U and V
+ * subsampled to 1/2 resolution) and generates the WebP string
+ *
+ * 4. RGBAToYUV420: Generates Y, U, V data (with color subsampling) from 32 bits
+ * per pixel RGBA data buffer. The resulting YUV data can be
+ * directly fed into the WebPEncode routine.
+ *
+ * 5. AdjustColorspace:
+ *
+ * 6. AdjustColorspaceBack:
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gd.h"
+#include "gd_errors.h"
+#ifdef HAVE_LIBVPX
+#include "webpimg.h"
+
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "vpx/vpx_decoder.h"
+#include "vpx/vp8dx.h"
+#include "vpx/vpx_encoder.h"
+#include "vpx/vp8cx.h"
+#include "gd.h"
+
+/*---------------------------------------------------------------------*
+ * color conversions *
+ *---------------------------------------------------------------------*/
+
+#ifndef inline
+# define inline __inline
+#endif
+static inline int clip(float v, int a, int b) {
+ return (v > b) ? b : (v < 0) ? 0 : (int)(v);
+}
+enum {
+ COLOR_RED = 0,
+ COLOR_GREEN = 1,
+ COLOR_BLUE = 2,
+ ALPHA_CHANNEL = 3
+};
+
+/* endian neutral extractions of RGBA from a 32 bit pixel */
+static const uint32 RED_SHIFT =
+ 8 * (sizeof(uint32) - 1 - COLOR_RED); /* 24 */
+static const uint32 GREEN_SHIFT =
+ 8 * (sizeof(uint32) - 1 - COLOR_GREEN); /* 16 */
+static const uint32 BLUE_SHIFT =
+ 8 * (sizeof(uint32) - 1 - COLOR_BLUE); /* 8 */
+static const uint32 ALPHA_SHIFT =
+ 8 * (sizeof(uint32) - 1 - ALPHA_CHANNEL); /* 0 */
+
+static inline int GetRed(const uint32* rgba) {
+ return gdTrueColorGetRed(*rgba);
+}
+
+static inline int GetGreen(const uint32* rgba) {
+ return gdTrueColorGetGreen(*rgba);
+}
+
+static inline int GetBlue(const uint32* rgba) {
+ return gdTrueColorGetBlue(*rgba);
+}
+
+enum { YUV_FRAC = 16 };
+
+static inline int clip_uv(int v) {
+ v = (v + (257 << (YUV_FRAC + 2 - 1))) >> (YUV_FRAC + 2);
+ return ((v & ~0xff) == 0) ? v : v < 0 ? 0u : 255u;
+}
+
+
+/* YUV <-----> RGB conversions */
+/* The exact naming is Y'CbCr, following the ITU-R BT.601 standard.
+ * More information at: http://en.wikipedia.org/wiki/YCbCr
+ */
+static inline int GetLumaY(int r, int g, int b) {
+ const int kRound = (1 << (YUV_FRAC - 1)) + (16 << YUV_FRAC);
+ // Y = 0.2569 * R + 0.5044 * G + 0.0979 * B + 16
+ const int luma = 16839 * r + 33059 * g + 6420 * b;
+ return (luma + kRound) >> YUV_FRAC;
+}
+
+static inline int GetLumaYfromPtr(uint32* rgba) {
+ const int r = GetRed(rgba);
+ const int g = GetGreen(rgba);
+ const int b = GetBlue(rgba);
+ return GetLumaY(r, g, b);
+}
+
+static inline int GetChromaU(int r, int g, int b) {
+ // U = -0.1483 * R - 0.2911 * G + 0.4394 * B + 128
+ return clip_uv(-9719 * r - 19081 * g + 28800 * b);
+}
+
+static inline int GetChromaV(int r, int g, int b) {
+ // V = 0.4394 * R - 0.3679 * G - 0.0715 * B + 128
+ return clip_uv(+28800 * r - 24116 * g - 4684 * b);
+}
+
+/* Converts YUV to RGB and writes into a 32 bit pixel in endian
+ * neutral fashion
+ */
+enum { RGB_FRAC = 16, RGB_HALF = (1 << RGB_FRAC) / 2,
+ RGB_RANGE_MIN = -227, RGB_RANGE_MAX = 256 + 226 };
+
+static int init_done = 0;
+static int16_t kVToR[256], kUToB[256];
+static int32_t kVToG[256], kUToG[256];
+static uint8_t kClip[RGB_RANGE_MAX - RGB_RANGE_MIN];
+
+static void InitTables() {
+ int i;
+ for (i = 0; i < 256; ++i) {
+ kVToR[i] = (89858 * (i - 128) + RGB_HALF) >> RGB_FRAC;
+ kUToG[i] = -22014 * (i - 128) + RGB_HALF;
+ kVToG[i] = -45773 * (i - 128);
+ kUToB[i] = (113618 * (i - 128) + RGB_HALF) >> RGB_FRAC;
+ }
+ for (i = RGB_RANGE_MIN; i < RGB_RANGE_MAX; ++i) {
+ const int j = ((i - 16) * 76283 + RGB_HALF) >> RGB_FRAC;
+ kClip[i - RGB_RANGE_MIN] = (j < 0) ? 0 : (j > 255) ? 255 : j;
+ }
+
+ init_done = 1;
+}
+
+static void ToRGB(int y, int u, int v, uint32* const dst) {
+ const int r_off = kVToR[v];
+ const int g_off = (kVToG[v] + kUToG[u]) >> RGB_FRAC;
+ const int b_off = kUToB[u];
+ const int r = kClip[y + r_off - RGB_RANGE_MIN];
+ const int g = kClip[y + g_off - RGB_RANGE_MIN];
+ const int b = kClip[y + b_off - RGB_RANGE_MIN];
+ *dst = (r << RED_SHIFT) | (g << GREEN_SHIFT) | (b << BLUE_SHIFT);
+}
+
+static inline uint32 get_le32(const uint8* const data) {
+ return data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
+}
+
+/* Returns the difference (in dB) between two images represented in YUV format
+ *
+ * Input:
+ * Y1/U1/V1: The Y/U/V data of the first image
+ * Y2/U2/V2: The Y/U/V data of the second image
+ *
+ * Returns the PSNR (http://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio)
+ * value computed bewteen the two images
+ */
+double GetPSNRYuv(const uint8* Y1,
+ const uint8* U1,
+ const uint8* V1,
+ const uint8* Y2,
+ const uint8* U2,
+ const uint8* V2,
+ int y_width,
+ int y_height) {
+ int x, y, row_idx;
+ const int uv_width = ((y_width + 1) >> 1);
+ const int uv_height = ((y_height + 1) >> 1);
+ double sse = 0., count = 0.;
+ for (y = 0; y < y_height; ++y) {
+ count += y_width;
+ row_idx = y * y_width;
+ for (x = 0; x < y_width; ++x) {
+ double diff = Y1[row_idx + x] - Y2[row_idx + x];
+ sse += diff * diff;
+ }
+ }
+ for (y = 0; y < uv_height; ++y) {
+ count += 2 * uv_width;
+ row_idx = y * uv_width;
+ for (x = 0; x < uv_width; ++x) {
+ const double diff_U = U1[row_idx + x] - U2[row_idx + x];
+ const double diff_V = V1[row_idx + x] - V2[row_idx + x];
+ sse += diff_U * diff_U + diff_V * diff_V;
+ }
+ }
+ return -4.3429448 * log(sse / (255. * 255. * count));
+}
+
+/* Returns the difference (in dB) between two images. One represented
+ * using Y,U,V vectors and the other is webp image data.
+ * Input:
+ * Y1/U1/V1: The Y/U/V data of the first image
+ * imgdata: data buffer containing webp image
+ * imgdata_size: size of the imgdata buffer
+ *
+ * Returns the PSNR value computed bewteen the two images
+ */
+double WebPGetPSNR(const uint8* Y1,
+ const uint8* U1,
+ const uint8* V1,
+ uint8* imgdata,
+ int imgdata_size) {
+ uint8* Y2 = NULL;
+ uint8* U2 = NULL;
+ uint8* V2 = NULL;
+ int w = 0, h = 0;
+ double psnr = 0;
+
+ WebPDecode(imgdata,
+ imgdata_size,
+ &Y2,
+ &U2,
+ &V2,
+ &w,
+ &h);
+
+ psnr = GetPSNRYuv(Y1, U1, V1, Y2, U2, V2, w, h);
+ free(Y2);
+
+ return psnr;
+}
+
+/*---------------------------------------------------------------------*
+ * Reading WebP *
+ *---------------------------------------------------------------------*/
+
+/* RIFF layout is:
+ * 0ffset tag
+ * 0...3 "RIFF" 4-byte tag
+ * 4...7 size of image data (including metadata) starting at offset 8
+ * 8...11 "WEBP" our form-type signature
+ * 12..15 "VP8 " 4-byte tags, describing the raw video format used
+ * 16..19 size of the raw WebP image data, starting at offset 20
+ * 20.... the WebP bytes
+ * There can be extra chunks after the "VP8 " chunk (ICMT, ICOP, ...)
+ * All 32-bits sizes are in little-endian order.
+ * Note: chunk data must be padded to multiple of 2 in size
+ */
+
+int SkipRiffHeader(const uint8** data_ptr, int *data_size_ptr) {
+ /* 20 bytes RIFF header 10 bytes VP8 header */
+ const int kHeaderSize = (20 + 10);
+ uint32 chunk_size = 0xffffffffu;
+
+ if (*data_size_ptr >= kHeaderSize && !memcmp(*data_ptr, "RIFF", 4)) {
+ if (memcmp(*data_ptr + 8, "WEBP", 4)) {
+ return 0; /* wrong image file signature */
+ } else {
+ const uint32 riff_size = get_le32(*data_ptr + 4);
+ if (memcmp(*data_ptr + 12, "VP8 ", 4)) {
+ return 0; /* invalid compression format */
+ }
+ chunk_size = get_le32(*data_ptr + 16);
+ if ((chunk_size > riff_size + 8) || (chunk_size & 1)) {
+ return 0; /* inconsistent size information. */
+ }
+ /* We have a RIFF container. Skip it. */
+ *data_ptr += 20;
+ *data_size_ptr -= 20;
+ }
+ }
+ return chunk_size;
+}
+
+/* Generate RGBA row from an YUV row (with width upsampling of chrome data)
+ * Input:
+ * 1, 2, 3. y_src, u_src, v_src - Pointers to input Y, U, V row data
+ * respectively. We reuse these variables, they iterate over all pixels in
+ * the row.
+ * 4. y_width: width of the Y image plane (aka image width)
+ * Output:
+ * 5. rgb_dst: pointer to the output rgb row. We reuse this variable, it
+ * iterates over all pixels in the row.
+ */
+static void YUV420toRGBLine(uint8* y_src,
+ uint8* u_src,
+ uint8* v_src,
+ int y_width,
+ uint32* rgb_dst) {
+ int x;
+ for (x = 0; x < (y_width >> 1); ++x) {
+ const int U = u_src[0];
+ const int V = v_src[0];
+ ToRGB(y_src[0], U, V, rgb_dst);
+ ToRGB(y_src[1], U, V, rgb_dst + 1);
+ ++u_src;
+ ++v_src;
+ y_src += 2;
+ rgb_dst += 2;
+ }
+ if (y_width & 1) { /* Rightmost pixel */
+ ToRGB(y_src[0], (*u_src), (*v_src), rgb_dst);
+ }
+}
+
+/* Converts from YUV (with color subsampling) such as produced by the WebPDecode
+ * routine into 32 bits per pixel RGBA data array. This data array can be
+ * directly used by the Leptonica Pix in-memory image format.
+ * Input:
+ * 1, 2, 3. Y, U, V: the input data buffers
+ * 4. pixwpl: the desired words per line corresponding to the supplied
+ * output pixdata.
+ * 5. width, height: the dimensions of the image whose data resides in Y,
+ * U, V.
+ * Output:
+ * 6. pixdata: the output data buffer. Caller should allocate
+ * height * pixwpl bytes of memory before calling this routine.
+ */
+void YUV420toRGBA(uint8* Y,
+ uint8* U,
+ uint8* V,
+ int words_per_line,
+ int width,
+ int height,
+ uint32* pixdata) {
+ int y_width = width;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_stride = uv_width;
+ int y;
+
+ if (!init_done)
+ InitTables();
+
+ /* note that the U, V upsampling in height is happening here as the U, V
+ * buffers sent to successive odd-even pair of lines is same.
+ */
+ for (y = 0; y < height; ++y) {
+ YUV420toRGBLine(Y + y * y_stride,
+ U + (y >> 1) * uv_stride,
+ V + (y >> 1) * uv_stride,
+ width,
+ pixdata + y * words_per_line);
+ }
+}
+
+void gd_YUV420toRGBA(uint8* Y,
+ uint8* U,
+ uint8* V,
+ gdImagePtr im) {
+ int width = im->sx;
+ int height = im->sy;
+ int y_width = width;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_stride = uv_width;
+ int y;
+
+ /* output im must be truecolor */
+ if (!im->trueColor) {
+ return;
+ }
+
+ if (!init_done)
+ InitTables();
+
+ /* note that the U, V upsampling in height is happening here as the U, V
+ * buffers sent to successive odd-even pair of lines is same.
+ */
+ for (y = 0; y < height; ++y) {
+ YUV420toRGBLine(Y + y * y_stride,
+ U + (y >> 1) * uv_stride,
+ V + (y >> 1) * uv_stride,
+ width,
+ (uint32 *)im->tpixels[y]);
+ }
+}
+
+static WebPResult VPXDecode(const uint8* data,
+ int data_size,
+ uint8** p_Y,
+ uint8** p_U,
+ uint8** p_V,
+ int* p_width,
+ int* p_height) {
+ vpx_codec_ctx_t dec;
+ vp8_postproc_cfg_t ppcfg;
+ WebPResult result = webp_failure;
+
+ if (!data || data_size <= 10 || !p_Y || !p_U || !p_V
+ || *p_Y != NULL || *p_U != NULL || *p_V != NULL) {
+ return webp_failure;
+ }
+
+ if (vpx_codec_dec_init(&dec,
+ &vpx_codec_vp8_dx_algo, NULL, 0) != VPX_CODEC_OK) {
+ return webp_failure;
+ }
+
+ ppcfg.post_proc_flag = VP8_NOFILTERING;
+ vpx_codec_control(&dec, VP8_SET_POSTPROC, &ppcfg);
+
+
+ if (vpx_codec_decode(&dec, data, data_size, NULL, 0) == VPX_CODEC_OK) {
+ vpx_codec_iter_t iter = NULL;
+ vpx_image_t* const img = vpx_codec_get_frame(&dec, &iter);
+ if (img) {
+ int y_width = img->d_w;
+ int y_height = img->d_h;
+ int y_stride = y_width;
+ int uv_width = (y_width + 1) >> 1;
+ int uv_stride = uv_width;
+ int uv_height = ((y_height + 1) >> 1);
+ int y;
+
+ *p_width = y_width;
+ *p_height = y_height;
+ if ((*p_Y = (uint8 *)(calloc(y_stride * y_height
+ + 2 * uv_stride * uv_height,
+ sizeof(uint8)))) != NULL) {
+ *p_U = *p_Y + y_height * y_stride;
+ *p_V = *p_U + uv_height * uv_stride;
+ for (y = 0; y < y_height; ++y) {
+ memcpy(*p_Y + y * y_stride,
+ img->planes[0] + y * img->stride[0],
+ y_width);
+ }
+ for (y = 0; y < uv_height; ++y) {
+ memcpy(*p_U + y * uv_stride,
+ img->planes[1] + y * img->stride[1],
+ uv_width);
+ memcpy(*p_V + y * uv_stride,
+ img->planes[2] + y * img->stride[2],
+ uv_width);
+ }
+ result = webp_success;
+ }
+ }
+ }
+ vpx_codec_destroy(&dec);
+
+ return result;
+}
+
+WebPResult WebPDecode(const uint8* data,
+ int data_size,
+ uint8** p_Y,
+ uint8** p_U,
+ uint8** p_V,
+ int* p_width,
+ int* p_height) {
+
+ const uint32 chunk_size = SkipRiffHeader(&data, &data_size);
+ if (!chunk_size) {
+ return webp_failure; /* unsupported RIFF header */
+ }
+
+ return VPXDecode(data, data_size, p_Y, p_U, p_V, p_width, p_height);
+}
+
+/*---------------------------------------------------------------------*
+ * Writing WebP *
+ *---------------------------------------------------------------------*/
+
+/* Takes a pair of RGBA row data as input and generates 2 rows of Y data and one
+ * row of subsampled U, V data as output
+ * Input:
+ * 1, 2. rgb_line1, rgb_line2 - input rgba rows
+ * 3. width - image width
+ * Outout:
+ * 4, 5, 6: Output Y, U, V row
+ */
+static void RGBALinepairToYUV420(uint32* rgb_line1,
+ uint32* rgb_line2,
+ int width,
+ uint8* Y_dst1,
+ uint8* Y_dst2,
+ uint8* u_dst,
+ uint8* v_dst) {
+ int x;
+ for (x = (width >> 1); x > 0; --x) {
+ const int sum_r =
+ GetRed(rgb_line1 + 0) + GetRed(rgb_line1 + 1) +
+ GetRed(rgb_line2 + 0) + GetRed(rgb_line2 + 1);
+ const int sum_g =
+ GetGreen(rgb_line1 + 0) + GetGreen(rgb_line1 + 1) +
+ GetGreen(rgb_line2 + 0) + GetGreen(rgb_line2 + 1);
+ const int sum_b =
+ GetBlue(rgb_line1 + 0) + GetBlue(rgb_line1 + 1) +
+ GetBlue(rgb_line2 + 0) + GetBlue(rgb_line2 + 1);
+
+ Y_dst1[0] = GetLumaYfromPtr(rgb_line1 + 0);
+ Y_dst1[1] = GetLumaYfromPtr(rgb_line1 + 1);
+ Y_dst2[0] = GetLumaYfromPtr(rgb_line2 + 0);
+ Y_dst2[1] = GetLumaYfromPtr(rgb_line2 + 1);
+
+ *u_dst++ = GetChromaU(sum_r, sum_g, sum_b);
+ *v_dst++ = GetChromaV(sum_r, sum_g, sum_b);
+
+ rgb_line1 += 2;
+ rgb_line2 += 2;
+ Y_dst1 += 2;
+ Y_dst2 += 2;
+ }
+
+ if (width & 1) { /* rightmost pixel. */
+ const int sum_r = GetRed(rgb_line1) + GetRed(rgb_line2);
+ const int sum_g = GetGreen(rgb_line1) + GetGreen(rgb_line2);
+ const int sum_b = GetBlue(rgb_line1) + GetBlue(rgb_line2);
+
+ Y_dst1[0] = GetLumaYfromPtr(rgb_line1);
+ Y_dst2[0] = GetLumaYfromPtr(rgb_line2);
+ *u_dst = GetChromaU(2 * sum_r, 2 * sum_g, 2 * sum_b);
+ *v_dst = GetChromaV(2 * sum_r, 2 * sum_g, 2 * sum_b);
+ }
+}
+
+/* Generates Y, U, V data (with color subsampling) from 32 bits
+ * per pixel RGBA data buffer. The resulting YUV data can be directly fed into
+ * the WebPEncode routine.
+ * Input:
+ * 1. pixdatainput rgba data buffer
+ * 2. words per line corresponding to pixdata
+ * 3, 4. image width and height respectively
+ * Output:
+ * 5, 6, 7. Output YUV data buffers
+ */
+void gd_RGBAToYUV420(gdImagePtr im2,
+ uint8* Y,
+ uint8* U,
+ uint8* V) {
+ int y_width = im2->sx;
+ int y_height = im2->sy;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_stride = uv_width;
+ int y;
+ gdImagePtr im = NULL;
+ int free_im = 0;
+
+ if (!im2->trueColor) {
+ /* Todo: Replace the color/YUV functions with our own and simplify
+ that should boost the conversion a bit as well, not only for
+ palette image. */
+ im = gdImageCreateTrueColor(im2->sx, im2->sy);
+ if (!im) {
+ gd_error("gd-webp error: cannot convert palette input to truecolor");
+ return;
+ }
+ gdImageCopy(im, im2, 0, 0, 0, 0, im->sx, im->sy);
+ free_im = 1;
+ } else {
+ im = im2;
+ }
+ for (y = 0; y < (y_height >> 1); ++y) {
+ RGBALinepairToYUV420((uint32 *)im->tpixels[2 * y],
+ (uint32 *)im->tpixels[2 * y + 1],
+ y_width,
+ Y + 2 * y * y_stride,
+ Y + (2 * y + 1) * y_stride,
+ U + y * uv_stride,
+ V + y * uv_stride);
+ }
+ if (y_height & 1) {
+ RGBALinepairToYUV420((uint32 *)im->tpixels[y_height - 1],
+ (uint32 *)im->tpixels[y_height - 1],
+ y_width,
+ Y + (y_height - 1) * y_stride,
+ Y + (y_height - 1) * y_stride,
+ U + (y_height >> 1) * uv_stride,
+ V + (y_height >> 1) * uv_stride);
+ }
+ if (free_im) {
+ gdImageDestroy(im);
+ }
+}
+
+/* Generates Y, U, V data (with color subsampling) from 32 bits
+ * per pixel RGBA data buffer. The resulting YUV data can be directly fed into
+ * the WebPEncode routine.
+ * Input:
+ * 1. pixdatainput rgba data buffer
+ * 2. words per line corresponding to pixdata
+ * 3, 4. image width and height respectively
+ * Output:
+ * 5, 6, 7. Output YUV data buffers
+ */
+void RGBAToYUV420(uint32* pixdata,
+ int words_per_line,
+ int width,
+ int height,
+ uint8* Y,
+ uint8* U,
+ uint8* V) {
+ int y_width = width;
+ int y_height = height;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_stride = uv_width;
+ int y;
+
+ for (y = 0; y < (y_height >> 1); ++y) {
+ RGBALinepairToYUV420(pixdata + 2 * y * words_per_line,
+ pixdata + (2 * y + 1) * words_per_line,
+ y_width,
+ Y + 2 * y * y_stride,
+ Y + (2 * y + 1) * y_stride,
+ U + y * uv_stride,
+ V + y * uv_stride);
+ }
+ if (y_height & 1) {
+ RGBALinepairToYUV420(pixdata + (y_height - 1) * words_per_line,
+ pixdata + (y_height - 1) * words_per_line,
+ y_width,
+ Y + (y_height - 1) * y_stride,
+ Y + (y_height - 1) * y_stride,
+ U + (y_height >> 1) * uv_stride,
+ V + (y_height >> 1) * uv_stride);
+ }
+}
+
+static int codec_ctl(vpx_codec_ctx_t *enc,
+ enum vp8e_enc_control_id id,
+ int value) {
+ const vpx_codec_err_t res = vpx_codec_control_(enc, id, value);
+ if (res != VPX_CODEC_OK) {
+ return webp_failure;
+ }
+ return webp_success;
+}
+
+static void SetupParams(vpx_codec_enc_cfg_t* cfg,
+ int QP) {
+ cfg->g_threads = 2;
+ cfg->rc_min_quantizer = QP;
+ cfg->rc_max_quantizer = QP;
+ cfg->kf_mode = VPX_KF_FIXED;
+}
+
+/* VPXEncode: Takes a Y, U, V data buffers (with color components U and V
+ * subsampled to 1/2 resolution) and generates the VPX string.
+ * Output VPX string is placed in the *p_out buffer. container_size
+ * indicates number of bytes to be left blank at the beginning of
+ * *p_out buffer to accommodate for a container header.
+ *
+ * Return: success/failure
+ */
+static WebPResult VPXEncode(const uint8* Y,
+ const uint8* U,
+ const uint8* V,
+ int y_width,
+ int y_height,
+ int y_stride,
+ int uv_width,
+ int uv_height,
+ int uv_stride,
+ int QP,
+ int container_size,
+ unsigned char** p_out,
+ int* p_out_size_bytes) {
+ vpx_codec_iface_t* iface = &vpx_codec_vp8_cx_algo;
+ vpx_codec_err_t res;
+ vpx_codec_enc_cfg_t cfg;
+ vpx_codec_ctx_t enc;
+ WebPResult result = webp_failure;
+ vpx_image_t img;
+
+ *p_out = NULL;
+ *p_out_size_bytes = 0;
+
+
+ /* validate input parameters. */
+ if (!p_out || !Y || !U || !V
+ || y_width <= 0 || y_height <= 0 || uv_width <= 0 || uv_height <= 0
+ || y_stride < y_width || uv_stride < uv_width
+ || QP < 0 || QP > 63) {
+ return webp_failure;
+ }
+
+ res = vpx_codec_enc_config_default(iface, &cfg, 0);
+ if (res != VPX_CODEC_OK) {
+ return webp_failure;
+ }
+
+ SetupParams(&cfg, QP);
+ cfg.g_w = y_width;
+ cfg.g_h = y_height;
+
+ res = vpx_codec_enc_init(&enc, iface, &cfg, 0);
+
+ if (res == VPX_CODEC_OK) {
+ codec_ctl(&enc, VP8E_SET_CPUUSED, 3);
+ codec_ctl(&enc, VP8E_SET_NOISE_SENSITIVITY, 0);
+ codec_ctl(&enc, VP8E_SET_SHARPNESS, 0);
+ codec_ctl(&enc, VP8E_SET_ENABLEAUTOALTREF, 0);
+ codec_ctl(&enc, VP8E_SET_ARNR_MAXFRAMES, 0);
+ codec_ctl(&enc, VP8E_SET_ARNR_TYPE, 0);
+ codec_ctl(&enc, VP8E_SET_ARNR_STRENGTH, 0);
+ codec_ctl(&enc, VP8E_SET_STATIC_THRESHOLD, 0);
+ codec_ctl(&enc, VP8E_SET_TOKEN_PARTITIONS, 2);
+
+ vpx_img_wrap(&img, IMG_FMT_I420,
+ y_width, y_height, 16, (uint8*)(Y));
+ img.planes[PLANE_Y] = (uint8*)(Y);
+ img.planes[PLANE_U] = (uint8*)(U);
+ img.planes[PLANE_V] = (uint8*)(V);
+ img.stride[PLANE_Y] = y_stride;
+ img.stride[PLANE_U] = uv_stride;
+ img.stride[PLANE_V] = uv_stride;
+
+ res = vpx_codec_encode(&enc, &img, 0, 1, 0, VPX_DL_BEST_QUALITY);
+
+ if (res == VPX_CODEC_OK) {
+ vpx_codec_iter_t iter = NULL;
+ const vpx_codec_cx_pkt_t* pkt = vpx_codec_get_cx_data(&enc, &iter);
+ if (pkt != NULL) {
+ *p_out = (unsigned char*)(calloc(container_size + pkt->data.frame.sz,
+ 1));
+
+ memcpy(*p_out + container_size,
+ (const void*)(pkt->data.frame.buf),
+ pkt->data.frame.sz);
+ *p_out_size_bytes = container_size + pkt->data.frame.sz;
+
+ result = webp_success;
+ }
+ }
+ }
+
+ vpx_codec_destroy(&enc);
+
+ return result;
+}
+
+WebPResult WebPEncode(const uint8* Y,
+ const uint8* U,
+ const uint8* V,
+ int y_width,
+ int y_height,
+ int y_stride,
+ int uv_width,
+ int uv_height,
+ int uv_stride,
+ int QP,
+ unsigned char** p_out,
+ int* p_out_size_bytes,
+ double *psnr) {
+
+ const int kRiffHeaderSize = 20;
+
+ if (VPXEncode(Y, U, V,
+ y_width, y_height, y_stride,
+ uv_width, uv_height, uv_stride,
+ QP, kRiffHeaderSize,
+ p_out, p_out_size_bytes) != webp_success) {
+ return webp_failure;
+ } else {
+ /* Write RIFF header */
+ const int img_size_bytes = *p_out_size_bytes - kRiffHeaderSize;
+ const int chunk_size = (img_size_bytes + 1) & ~1; /* make size even */
+ const int riff_size = chunk_size + 12;
+ const uint8_t kRiffHeader[20] = { 'R', 'I', 'F', 'F',
+ (riff_size >> 0) & 255,
+ (riff_size >> 8) & 255,
+ (riff_size >> 16) & 255,
+ (riff_size >> 24) & 255,
+ 'W', 'E', 'B', 'P',
+ 'V', 'P', '8', ' ',
+ (chunk_size >> 0) & 255,
+ (chunk_size >> 8) & 255,
+ (chunk_size >> 16) & 255,
+ (chunk_size >> 24) & 255 };
+ memcpy(*p_out, kRiffHeader, kRiffHeaderSize);
+
+ if (psnr) {
+ *psnr = WebPGetPSNR(Y, U, V, *p_out, *p_out_size_bytes);
+ }
+
+ return webp_success;
+ }
+}
+
+void AdjustColorspace(uint8* Y, uint8* U, uint8* V, int width, int height) {
+ int y_width = width;
+ int y_height = height;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_height = ((y_height + 1) >> 1);
+ int uv_stride = uv_width;
+ int x, y;
+ /* convert luma */
+ for (y = 0; y < y_height; ++y) {
+ uint8* const Yrow = Y + y * y_stride;
+ for (x = 0; x < y_width; ++x) {
+ /* maps [0..255] to [16..235] */
+ Yrow[x] = ((Yrow[x] * 55 + 32) >> 6) + 16;
+ }
+ }
+ /* convert chroma */
+ for (y = 0; y < uv_height; ++y) {
+ uint8* const Urow = U + y * uv_stride;
+ uint8* const Vrow = V + y * uv_stride;
+ for (x = 0; x < uv_width; ++x) {
+ /* maps [0..255] to [16..240] */
+ Urow[x] = (((Urow[x] - 127) * 7) >> 3) + 128;
+ Vrow[x] = (((Vrow[x] - 127) * 7) >> 3) + 128;
+ }
+ }
+}
+
+void AdjustColorspaceBack(uint8* Y, uint8* U, uint8* V, int width, int height) {
+ int y_width = width;
+ int y_height = height;
+ int y_stride = y_width;
+ int uv_width = ((y_width + 1) >> 1);
+ int uv_height = ((y_height + 1) >> 1);
+ int uv_stride = uv_width;
+ int x, y;
+ /* convert luma */
+ for (y = 0; y < y_height; ++y) {
+ uint8* const Yrow = Y + y * y_stride;
+ for (x = 0; x < y_width; ++x) {
+ /* maps [16..235] to [0..255] */
+ const int v = ((Yrow[x] - 16) * 149 + 64) >> 7;
+ Yrow[x] = (v < 0) ? 0 : (v > 255) ? 255u : v;
+ }
+ }
+ /* convert chroma */
+ for (y = 0; y < uv_height; ++y) {
+ uint8* const Urow = U + y * uv_stride;
+ uint8* const Vrow = V + y * uv_stride;
+ for (x = 0; x < uv_width; ++x) {
+ /* maps [0..255] to [16..240] */
+ const int ru = (((Urow[x] - 128) * 73) >> 6) + 128;
+ const int rv = (((Vrow[x] - 128) * 73) >> 6) + 128;
+ Urow[x] = (ru < 0) ? 0 : (ru > 255) ? 255u : ru;
+ Vrow[x] = (rv < 0) ? 0 : (rv > 255) ? 255u : rv;
+ }
+ }
+}
+
+WebPResult WebPGetInfo(const uint8* data,
+ int data_size,
+ int *width,
+ int *height) {
+ const uint32 chunk_size = SkipRiffHeader(&data, &data_size);
+
+ if (width) *width = 0;
+ if (height) *height = 0;
+
+ if (!chunk_size) {
+ return webp_failure; /* unsupported RIFF header */
+ }
+
+ /* Validate raw video data */
+ if (data_size < 10) {
+ return webp_failure; /* not enough data */
+ }
+
+ /* check signature */
+ if (data[3] != 0x9d || data[4] != 0x01 || data[5] != 0x2a) {
+ return webp_failure; /* Wrong signature. */
+ } else {
+ const uint32 bits = data[0] | (data[1] << 8) | (data[2] << 16);
+
+ if ((bits & 1)) { /* Not a keyframe. */
+ return webp_failure;
+ } else {
+ const int profile = (bits >> 1) & 7;
+ const int show_frame = (bits >> 4) & 1;
+ const uint32 partition_length = (bits >> 5);
+
+ if (profile > 3) {
+ return webp_failure; /* unknown profile */
+ }
+ if (!show_frame) {
+ return webp_failure; /* first frame is invisible! */
+ }
+ if (partition_length >= chunk_size) {
+ return webp_failure; /* inconsistent size information. */
+ } else {
+ const int w = ((data[7] << 8) | data[6]) & 0x3fff;
+ const int h = ((data[9] << 8) | data[8]) & 0x3fff;
+ if (width) *width = w;
+ if (height) *height = h;
+
+ return webp_success;
+ }
+ }
+ }
+ return webp_failure;
+}
+#endif /* HAVE_LIBVPX */