mirror of
https://github.com/webmproject/libwebp.git
synced 2024-12-28 14:38:21 +01:00
437999fb77
VP8-lossy will now avoid writing an ALPH chunk if the alpha values are trivial. + changed DumpPicture() accordingly in cwebp + prevented the -d option to be active with lossless (DumpPicture wouldn't work). Change-Id: I34fdb108a2b6207e93fa6cd00b1d2509a8e1dc4b
815 lines
25 KiB
C
815 lines
25 KiB
C
// Copyright 2011 Google Inc. All Rights Reserved.
|
|
//
|
|
// 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/
|
|
// -----------------------------------------------------------------------------
|
|
//
|
|
// WebPPicture utils: colorspace conversion, crop, ...
|
|
//
|
|
// Author: Skal (pascal.massimino@gmail.com)
|
|
|
|
#include <assert.h>
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
|
|
#include "./vp8enci.h"
|
|
#include "../utils/rescaler.h"
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
extern "C" {
|
|
#endif
|
|
|
|
#define HALVE(x) (((x) + 1) >> 1)
|
|
|
|
//------------------------------------------------------------------------------
|
|
// WebPPicture
|
|
//------------------------------------------------------------------------------
|
|
|
|
int WebPPictureAlloc(WebPPicture* const picture) {
|
|
if (picture != NULL) {
|
|
const WebPEncCSP uv_csp = picture->colorspace & WEBP_CSP_UV_MASK;
|
|
const int has_alpha = picture->colorspace & WEBP_CSP_ALPHA_BIT;
|
|
const int width = picture->width;
|
|
const int height = picture->height;
|
|
|
|
if (!picture->use_argb_input) {
|
|
const int y_stride = width;
|
|
const int uv_width = HALVE(width);
|
|
const int uv_height = HALVE(height);
|
|
const int uv_stride = uv_width;
|
|
int uv0_stride = 0;
|
|
int a_width, a_stride;
|
|
uint64_t y_size, uv_size, uv0_size, a_size, total_size;
|
|
uint8_t* mem;
|
|
|
|
// U/V
|
|
switch (uv_csp) {
|
|
case WEBP_YUV420:
|
|
break;
|
|
#ifdef WEBP_EXPERIMENTAL_FEATURES
|
|
case WEBP_YUV400: // for now, we'll just reset the U/V samples
|
|
break;
|
|
case WEBP_YUV422:
|
|
uv0_stride = uv_width;
|
|
break;
|
|
case WEBP_YUV444:
|
|
uv0_stride = width;
|
|
break;
|
|
#endif
|
|
default:
|
|
return 0;
|
|
}
|
|
uv0_size = height * uv0_stride;
|
|
|
|
// alpha
|
|
a_width = has_alpha ? width : 0;
|
|
a_stride = a_width;
|
|
y_size = (uint64_t)y_stride * height;
|
|
uv_size = (uint64_t)uv_stride * uv_height;
|
|
a_size = (uint64_t)a_stride * height;
|
|
|
|
total_size = y_size + a_size + 2 * uv_size + 2 * uv0_size;
|
|
|
|
// Security and validation checks
|
|
if (width <= 0 || height <= 0 || // luma/alpha param error
|
|
uv_width < 0 || uv_height < 0 || // u/v param error
|
|
y_size >= (1ULL << 40) || // reasonable global size
|
|
(size_t)total_size != total_size) { // overflow on 32bit
|
|
return 0;
|
|
}
|
|
picture->y_stride = y_stride;
|
|
picture->uv_stride = uv_stride;
|
|
picture->a_stride = a_stride;
|
|
picture->uv0_stride = uv0_stride;
|
|
WebPPictureFree(picture); // erase previous buffer
|
|
mem = (uint8_t*)malloc((size_t)total_size);
|
|
if (mem == NULL) return 0;
|
|
|
|
picture->y = mem;
|
|
mem += y_size;
|
|
|
|
picture->u = mem;
|
|
mem += uv_size;
|
|
picture->v = mem;
|
|
mem += uv_size;
|
|
|
|
if (a_size) {
|
|
picture->a = mem;
|
|
mem += a_size;
|
|
}
|
|
if (uv0_size) {
|
|
picture->u0 = mem;
|
|
mem += uv0_size;
|
|
picture->v0 = mem;
|
|
mem += uv0_size;
|
|
}
|
|
} else {
|
|
#ifdef USE_LOSSLESS_ENCODER
|
|
const uint64_t argb_size = (uint64_t)width * height;
|
|
const uint64_t total_size = argb_size * sizeof(*picture->argb);
|
|
if (width <= 0 || height <= 0 ||
|
|
argb_size >= (1ULL << 40) ||
|
|
(size_t)total_size != total_size) {
|
|
return 0;
|
|
}
|
|
WebPPictureFree(picture); // erase previous buffer
|
|
picture->argb = (uint32_t*)malloc(total_size);
|
|
if (picture->argb == NULL) return 0;
|
|
picture->argb_stride = width;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
// Grab the 'specs' (writer, *opaque, width, height...) from 'src' and copy them
|
|
// into 'dst'. Mark 'dst' as not owning any memory. 'src' can be NULL.
|
|
static void WebPPictureGrabSpecs(const WebPPicture* const src,
|
|
WebPPicture* const dst) {
|
|
if (src != NULL) *dst = *src;
|
|
dst->y = dst->u = dst->v = NULL;
|
|
dst->u0 = dst->v0 = NULL;
|
|
dst->a = NULL;
|
|
#ifdef USE_LOSSLESS_ENCODER
|
|
dst->argb = NULL;
|
|
#endif
|
|
}
|
|
|
|
// Release memory owned by 'picture'.
|
|
void WebPPictureFree(WebPPicture* const picture) {
|
|
if (picture != NULL) {
|
|
free(picture->y);
|
|
#ifdef USE_LOSSLESS_ENCODER
|
|
free(picture->argb);
|
|
#endif
|
|
WebPPictureGrabSpecs(NULL, picture);
|
|
}
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Picture copying
|
|
|
|
// Not worth moving to dsp/enc.c (only used here).
|
|
static void CopyPlane(const uint8_t* src, int src_stride,
|
|
uint8_t* dst, int dst_stride, int width, int height) {
|
|
while (height-- > 0) {
|
|
memcpy(dst, src, width);
|
|
src += src_stride;
|
|
dst += dst_stride;
|
|
}
|
|
}
|
|
|
|
int WebPPictureCopy(const WebPPicture* const src, WebPPicture* const dst) {
|
|
if (src == NULL || dst == NULL) return 0;
|
|
if (src == dst) return 1;
|
|
|
|
WebPPictureGrabSpecs(src, dst);
|
|
if (!WebPPictureAlloc(dst)) return 0;
|
|
|
|
if (!src->use_argb_input) {
|
|
CopyPlane(src->y, src->y_stride,
|
|
dst->y, dst->y_stride, dst->width, dst->height);
|
|
CopyPlane(src->u, src->uv_stride,
|
|
dst->u, dst->uv_stride, HALVE(dst->width), HALVE(dst->height));
|
|
CopyPlane(src->v, src->uv_stride,
|
|
dst->v, dst->uv_stride, HALVE(dst->width), HALVE(dst->height));
|
|
if (dst->a != NULL) {
|
|
CopyPlane(src->a, src->a_stride,
|
|
dst->a, dst->a_stride, dst->width, dst->height);
|
|
}
|
|
#ifdef WEBP_EXPERIMENTAL_FEATURES
|
|
if (dst->u0 != NULL) {
|
|
int uv0_width = src->width;
|
|
if ((dst->colorspace & WEBP_CSP_UV_MASK) == WEBP_YUV422) {
|
|
uv0_width = HALVE(uv0_width);
|
|
}
|
|
CopyPlane(src->u0, src->uv0_stride,
|
|
dst->u0, dst->uv0_stride, uv0_width, dst->height);
|
|
CopyPlane(src->v0, src->uv0_stride,
|
|
dst->v0, dst->uv0_stride, uv0_width, dst->height);
|
|
}
|
|
#endif
|
|
} else {
|
|
#ifdef USE_LOSSLESS_ENCODER
|
|
CopyPlane((uint8_t*)src->argb, 4 * src->argb_stride,
|
|
(uint8_t*)dst->argb, 4 * dst->argb_stride,
|
|
4 * dst->width, dst->height);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Picture cropping
|
|
|
|
int WebPPictureCrop(WebPPicture* const pic,
|
|
int left, int top, int width, int height) {
|
|
WebPPicture tmp;
|
|
|
|
if (pic == NULL) return 0;
|
|
if (width <= 0 || height <= 0) return 0;
|
|
if (left < 0 || ((left + width + 1) & ~1) > pic->width) return 0;
|
|
if (top < 0 || ((top + height + 1) & ~1) > pic->height) return 0;
|
|
|
|
WebPPictureGrabSpecs(pic, &tmp);
|
|
tmp.width = width;
|
|
tmp.height = height;
|
|
if (!WebPPictureAlloc(&tmp)) return 0;
|
|
|
|
{
|
|
const int y_offset = top * pic->y_stride + left;
|
|
const int uv_offset = (top / 2) * pic->uv_stride + left / 2;
|
|
CopyPlane(pic->y + y_offset, pic->y_stride,
|
|
tmp.y, tmp.y_stride, width, height);
|
|
CopyPlane(pic->u + uv_offset, pic->uv_stride,
|
|
tmp.u, tmp.uv_stride, HALVE(width), HALVE(height));
|
|
CopyPlane(pic->v + uv_offset, pic->uv_stride,
|
|
tmp.v, tmp.uv_stride, HALVE(width), HALVE(height));
|
|
}
|
|
|
|
if (tmp.a != NULL) {
|
|
const int a_offset = top * pic->a_stride + left;
|
|
CopyPlane(pic->a + a_offset, pic->a_stride,
|
|
tmp.a, tmp.a_stride, width, height);
|
|
}
|
|
#ifdef WEBP_EXPERIMENTAL_FEATURES
|
|
if (tmp.u0 != NULL) {
|
|
int w = width;
|
|
int l = left;
|
|
if (tmp.colorspace == WEBP_YUV422) {
|
|
w = HALVE(w);
|
|
l = HALVE(l);
|
|
}
|
|
CopyPlane(pic->u0 + top * pic->uv0_stride + l, pic->uv0_stride,
|
|
tmp.u0, tmp.uv0_stride, w, l);
|
|
CopyPlane(pic->v0 + top * pic->uv0_stride + l, pic->uv0_stride,
|
|
tmp.v0, tmp.uv0_stride, w, l);
|
|
}
|
|
#endif
|
|
|
|
WebPPictureFree(pic);
|
|
*pic = tmp;
|
|
return 1;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Simple picture rescaler
|
|
|
|
static void RescalePlane(const uint8_t* src,
|
|
int src_width, int src_height, int src_stride,
|
|
uint8_t* dst,
|
|
int dst_width, int dst_height, int dst_stride,
|
|
int32_t* const work) {
|
|
WebPRescaler rescaler;
|
|
int y = 0;
|
|
|
|
WebPRescalerInit(&rescaler, src_width, src_height,
|
|
dst, dst_width, dst_height, dst_stride,
|
|
1,
|
|
src_width, dst_width,
|
|
src_height, dst_height,
|
|
work);
|
|
memset(work, 0, 2 * dst_width * sizeof(*work));
|
|
while (y < src_height) {
|
|
const int num_lines_in =
|
|
WebPRescalerImport(&rescaler, src_height - y, src, src_stride);
|
|
y += num_lines_in;
|
|
src += num_lines_in * src_stride;
|
|
WebPRescalerExport(&rescaler);
|
|
}
|
|
}
|
|
|
|
int WebPPictureRescale(WebPPicture* const pic, int width, int height) {
|
|
WebPPicture tmp;
|
|
int prev_width, prev_height;
|
|
int32_t* work;
|
|
|
|
if (pic == NULL) return 0;
|
|
prev_width = pic->width;
|
|
prev_height = pic->height;
|
|
// if width is unspecified, scale original proportionally to height ratio.
|
|
if (width == 0) {
|
|
width = (prev_width * height + prev_height / 2) / prev_height;
|
|
}
|
|
// if height is unspecified, scale original proportionally to width ratio.
|
|
if (height == 0) {
|
|
height = (prev_height * width + prev_width / 2) / prev_width;
|
|
}
|
|
// Check if the overall dimensions still make sense.
|
|
if (width <= 0 || height <= 0) return 0;
|
|
|
|
WebPPictureGrabSpecs(pic, &tmp);
|
|
tmp.width = width;
|
|
tmp.height = height;
|
|
if (!WebPPictureAlloc(&tmp)) return 0;
|
|
|
|
work = (int32_t*)malloc(2 * width * sizeof(*work));
|
|
if (work == NULL) {
|
|
WebPPictureFree(&tmp);
|
|
return 0;
|
|
}
|
|
|
|
RescalePlane(pic->y, prev_width, prev_height, pic->y_stride,
|
|
tmp.y, width, height, tmp.y_stride, work);
|
|
RescalePlane(pic->u,
|
|
HALVE(prev_width), HALVE(prev_height), pic->uv_stride,
|
|
tmp.u,
|
|
HALVE(width), HALVE(height), tmp.uv_stride, work);
|
|
RescalePlane(pic->v,
|
|
HALVE(prev_width), HALVE(prev_height), pic->uv_stride,
|
|
tmp.v,
|
|
HALVE(width), HALVE(height), tmp.uv_stride, work);
|
|
|
|
if (tmp.a != NULL) {
|
|
RescalePlane(pic->a, prev_width, prev_height, pic->a_stride,
|
|
tmp.a, width, height, tmp.a_stride, work);
|
|
}
|
|
#ifdef WEBP_EXPERIMENTAL_FEATURES
|
|
if (tmp.u0 != NULL) {
|
|
int s = 1;
|
|
if ((tmp.colorspace & WEBP_CSP_UV_MASK) == WEBP_YUV422) {
|
|
s = 2;
|
|
}
|
|
RescalePlane(
|
|
pic->u0, (prev_width + s / 2) / s, prev_height, pic->uv0_stride,
|
|
tmp.u0, (width + s / 2) / s, height, tmp.uv0_stride, work);
|
|
RescalePlane(
|
|
pic->v0, (prev_width + s / 2) / s, prev_height, pic->uv0_stride,
|
|
tmp.v0, (width + s / 2) / s, height, tmp.uv0_stride, work);
|
|
}
|
|
#endif
|
|
|
|
WebPPictureFree(pic);
|
|
free(work);
|
|
*pic = tmp;
|
|
return 1;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Write-to-memory
|
|
|
|
typedef struct {
|
|
uint8_t** mem;
|
|
size_t max_size;
|
|
size_t* size;
|
|
} WebPMemoryWriter;
|
|
|
|
static void WebPMemoryWriterInit(WebPMemoryWriter* const writer) {
|
|
*writer->mem = NULL;
|
|
*writer->size = 0;
|
|
writer->max_size = 0;
|
|
}
|
|
|
|
static int WebPMemoryWrite(const uint8_t* data, size_t data_size,
|
|
const WebPPicture* const picture) {
|
|
WebPMemoryWriter* const w = (WebPMemoryWriter*)picture->custom_ptr;
|
|
size_t next_size;
|
|
if (w == NULL) {
|
|
return 1;
|
|
}
|
|
next_size = (*w->size) + data_size;
|
|
if (next_size > w->max_size) {
|
|
uint8_t* new_mem;
|
|
size_t next_max_size = w->max_size * 2;
|
|
if (next_max_size < next_size) next_max_size = next_size;
|
|
if (next_max_size < 8192) next_max_size = 8192;
|
|
new_mem = (uint8_t*)malloc(next_max_size);
|
|
if (new_mem == NULL) {
|
|
return 0;
|
|
}
|
|
if ((*w->size) > 0) {
|
|
memcpy(new_mem, *w->mem, *w->size);
|
|
}
|
|
free(*w->mem);
|
|
*w->mem = new_mem;
|
|
w->max_size = next_max_size;
|
|
}
|
|
if (data_size > 0) {
|
|
memcpy((*w->mem) + (*w->size), data, data_size);
|
|
*w->size += data_size;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// RGB -> YUV conversion
|
|
// The exact naming is Y'CbCr, following the ITU-R BT.601 standard.
|
|
// More information at: http://en.wikipedia.org/wiki/YCbCr
|
|
// Y = 0.2569 * R + 0.5044 * G + 0.0979 * B + 16
|
|
// U = -0.1483 * R - 0.2911 * G + 0.4394 * B + 128
|
|
// V = 0.4394 * R - 0.3679 * G - 0.0715 * B + 128
|
|
// We use 16bit fixed point operations.
|
|
|
|
enum { YUV_FRAC = 16 };
|
|
|
|
static WEBP_INLINE int clip_uv(int v) {
|
|
v = (v + (257 << (YUV_FRAC + 2 - 1))) >> (YUV_FRAC + 2);
|
|
return ((v & ~0xff) == 0) ? v : (v < 0) ? 0 : 255;
|
|
}
|
|
|
|
static WEBP_INLINE int rgb_to_y(int r, int g, int b) {
|
|
const int kRound = (1 << (YUV_FRAC - 1)) + (16 << YUV_FRAC);
|
|
const int luma = 16839 * r + 33059 * g + 6420 * b;
|
|
return (luma + kRound) >> YUV_FRAC; // no need to clip
|
|
}
|
|
|
|
static WEBP_INLINE int rgb_to_u(int r, int g, int b) {
|
|
return clip_uv(-9719 * r - 19081 * g + 28800 * b);
|
|
}
|
|
|
|
static WEBP_INLINE int rgb_to_v(int r, int g, int b) {
|
|
return clip_uv(+28800 * r - 24116 * g - 4684 * b);
|
|
}
|
|
|
|
// TODO: we can do better than simply 2x2 averaging on U/V samples.
|
|
#define SUM4(ptr) ((ptr)[0] + (ptr)[step] + \
|
|
(ptr)[rgb_stride] + (ptr)[rgb_stride + step])
|
|
#define SUM2H(ptr) (2 * (ptr)[0] + 2 * (ptr)[step])
|
|
#define SUM2V(ptr) (2 * (ptr)[0] + 2 * (ptr)[rgb_stride])
|
|
#define SUM1(ptr) (4 * (ptr)[0])
|
|
#define RGB_TO_UV(x, y, SUM) { \
|
|
const int src = (2 * (step * (x) + (y) * rgb_stride)); \
|
|
const int dst = (x) + (y) * picture->uv_stride; \
|
|
const int r = SUM(r_ptr + src); \
|
|
const int g = SUM(g_ptr + src); \
|
|
const int b = SUM(b_ptr + src); \
|
|
picture->u[dst] = rgb_to_u(r, g, b); \
|
|
picture->v[dst] = rgb_to_v(r, g, b); \
|
|
}
|
|
|
|
#define RGB_TO_UV0(x_in, x_out, y, SUM) { \
|
|
const int src = (step * (x_in) + (y) * rgb_stride); \
|
|
const int dst = (x_out) + (y) * picture->uv0_stride; \
|
|
const int r = SUM(r_ptr + src); \
|
|
const int g = SUM(g_ptr + src); \
|
|
const int b = SUM(b_ptr + src); \
|
|
picture->u0[dst] = rgb_to_u(r, g, b); \
|
|
picture->v0[dst] = rgb_to_v(r, g, b); \
|
|
}
|
|
|
|
static void MakeGray(WebPPicture* const picture) {
|
|
int y;
|
|
const int uv_width = HALVE(picture->width);
|
|
const int uv_height = HALVE(picture->height);
|
|
for (y = 0; y < uv_height; ++y) {
|
|
memset(picture->u + y * picture->uv_stride, 128, uv_width);
|
|
memset(picture->v + y * picture->uv_stride, 128, uv_width);
|
|
}
|
|
}
|
|
|
|
static int Import(WebPPicture* const picture,
|
|
const uint8_t* const rgb, int rgb_stride,
|
|
int step, int swap_rb, int import_alpha) {
|
|
const WebPEncCSP uv_csp = picture->colorspace & WEBP_CSP_UV_MASK;
|
|
int x, y;
|
|
const uint8_t* const r_ptr = rgb + (swap_rb ? 2 : 0);
|
|
const uint8_t* const g_ptr = rgb + 1;
|
|
const uint8_t* const b_ptr = rgb + (swap_rb ? 0 : 2);
|
|
const int width = picture->width;
|
|
const int height = picture->height;
|
|
|
|
if (!picture->use_argb_input) {
|
|
// Import luma plane
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < width; ++x) {
|
|
const int offset = step * x + y * rgb_stride;
|
|
picture->y[x + y * picture->y_stride] =
|
|
rgb_to_y(r_ptr[offset], g_ptr[offset], b_ptr[offset]);
|
|
}
|
|
}
|
|
|
|
// Downsample U/V plane
|
|
if (uv_csp != WEBP_YUV400) {
|
|
for (y = 0; y < (height >> 1); ++y) {
|
|
for (x = 0; x < (width >> 1); ++x) {
|
|
RGB_TO_UV(x, y, SUM4);
|
|
}
|
|
if (picture->width & 1) {
|
|
RGB_TO_UV(x, y, SUM2V);
|
|
}
|
|
}
|
|
if (height & 1) {
|
|
for (x = 0; x < (width >> 1); ++x) {
|
|
RGB_TO_UV(x, y, SUM2H);
|
|
}
|
|
if (width & 1) {
|
|
RGB_TO_UV(x, y, SUM1);
|
|
}
|
|
}
|
|
|
|
#ifdef WEBP_EXPERIMENTAL_FEATURES
|
|
// Store original U/V samples too
|
|
if (uv_csp == WEBP_YUV422) {
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < (width >> 1); ++x) {
|
|
RGB_TO_UV0(2 * x, x, y, SUM2H);
|
|
}
|
|
if (width & 1) {
|
|
RGB_TO_UV0(2 * x, x, y, SUM1);
|
|
}
|
|
}
|
|
} else if (uv_csp == WEBP_YUV444) {
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < width; ++x) {
|
|
RGB_TO_UV0(x, x, y, SUM1);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
} else {
|
|
MakeGray(picture);
|
|
}
|
|
|
|
if (import_alpha) {
|
|
const uint8_t* const a_ptr = rgb + 3;
|
|
assert(step >= 4);
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < width; ++x) {
|
|
picture->a[x + y * picture->a_stride] =
|
|
a_ptr[step * x + y * rgb_stride];
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
#ifdef USE_LOSSLESS_ENCODER
|
|
if (!import_alpha) {
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < width; ++x) {
|
|
const int offset = step * x + y * rgb_stride;
|
|
const uint32_t argb =
|
|
0xff000000 |
|
|
(r_ptr[offset] << 16) |
|
|
(g_ptr[offset] << 8) |
|
|
(b_ptr[offset]);
|
|
picture->argb[x + y * picture->argb_stride] = argb;
|
|
}
|
|
}
|
|
} else {
|
|
const uint8_t* const a_ptr = rgb + 3;
|
|
assert(step >= 4);
|
|
for (y = 0; y < height; ++y) {
|
|
for (x = 0; x < width; ++x) {
|
|
const int offset = step * x + y * rgb_stride;
|
|
const uint32_t argb =
|
|
(a_ptr[offset] << 24) |
|
|
(r_ptr[offset] << 16) |
|
|
(g_ptr[offset] << 8) |
|
|
(b_ptr[offset]);
|
|
picture->argb[x + y * picture->argb_stride] = argb;
|
|
}
|
|
}
|
|
}
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 1;
|
|
}
|
|
#undef SUM4
|
|
#undef SUM2V
|
|
#undef SUM2H
|
|
#undef SUM1
|
|
#undef RGB_TO_UV
|
|
|
|
int WebPPictureImportRGB(WebPPicture* const picture,
|
|
const uint8_t* const rgb, int rgb_stride) {
|
|
picture->colorspace &= ~WEBP_CSP_ALPHA_BIT;
|
|
if (!WebPPictureAlloc(picture)) return 0;
|
|
return Import(picture, rgb, rgb_stride, 3, 0, 0);
|
|
}
|
|
|
|
int WebPPictureImportBGR(WebPPicture* const picture,
|
|
const uint8_t* const rgb, int rgb_stride) {
|
|
picture->colorspace &= ~WEBP_CSP_ALPHA_BIT;
|
|
if (!WebPPictureAlloc(picture)) return 0;
|
|
return Import(picture, rgb, rgb_stride, 3, 1, 0);
|
|
}
|
|
|
|
int WebPPictureImportRGBA(WebPPicture* const picture,
|
|
const uint8_t* const rgba, int rgba_stride) {
|
|
picture->colorspace |= WEBP_CSP_ALPHA_BIT;
|
|
if (!WebPPictureAlloc(picture)) return 0;
|
|
return Import(picture, rgba, rgba_stride, 4, 0, 1);
|
|
}
|
|
|
|
int WebPPictureImportBGRA(WebPPicture* const picture,
|
|
const uint8_t* const rgba, int rgba_stride) {
|
|
picture->colorspace |= WEBP_CSP_ALPHA_BIT;
|
|
if (!WebPPictureAlloc(picture)) return 0;
|
|
return Import(picture, rgba, rgba_stride, 4, 1, 1);
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Helper: clean up fully transparent area to help compressibility.
|
|
|
|
#define SIZE 8
|
|
#define SIZE2 (SIZE / 2)
|
|
static int is_transparent_area(const uint8_t* ptr, int stride, int size) {
|
|
int y, x;
|
|
for (y = 0; y < size; ++y) {
|
|
for (x = 0; x < size; ++x) {
|
|
if (ptr[x]) {
|
|
return 0;
|
|
}
|
|
}
|
|
ptr += stride;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static WEBP_INLINE void flatten(uint8_t* ptr, int v, int stride, int size) {
|
|
int y;
|
|
for (y = 0; y < size; ++y) {
|
|
memset(ptr, v, size);
|
|
ptr += stride;
|
|
}
|
|
}
|
|
|
|
void WebPCleanupTransparentArea(WebPPicture* const pic) {
|
|
int x, y, w, h;
|
|
const uint8_t* a_ptr;
|
|
int values[3] = { 0 };
|
|
|
|
if (pic == NULL) return;
|
|
|
|
a_ptr = pic->a;
|
|
if (a_ptr == NULL) return; // nothing to do
|
|
|
|
w = pic->width / SIZE;
|
|
h = pic->height / SIZE;
|
|
for (y = 0; y < h; ++y) {
|
|
int need_reset = 1;
|
|
for (x = 0; x < w; ++x) {
|
|
const int off_a = (y * pic->a_stride + x) * SIZE;
|
|
const int off_y = (y * pic->y_stride + x) * SIZE;
|
|
const int off_uv = (y * pic->uv_stride + x) * SIZE2;
|
|
if (is_transparent_area(a_ptr + off_a, pic->a_stride, SIZE)) {
|
|
if (need_reset) {
|
|
values[0] = pic->y[off_y];
|
|
values[1] = pic->u[off_uv];
|
|
values[2] = pic->v[off_uv];
|
|
need_reset = 0;
|
|
}
|
|
flatten(pic->y + off_y, values[0], pic->y_stride, SIZE);
|
|
flatten(pic->u + off_uv, values[1], pic->uv_stride, SIZE2);
|
|
flatten(pic->v + off_uv, values[2], pic->uv_stride, SIZE2);
|
|
} else {
|
|
need_reset = 1;
|
|
}
|
|
}
|
|
// ignore the left-overs on right/bottom
|
|
}
|
|
}
|
|
|
|
#undef SIZE
|
|
#undef SIZE2
|
|
|
|
// Checking for the presence of non-opaque alpha.
|
|
int WebPPictureHasTransparency(const WebPPicture* const pic) {
|
|
if (pic == NULL) return 0;
|
|
if (!pic->use_argb_input) {
|
|
int x, y;
|
|
const uint8_t* alpha = pic->a;
|
|
if (alpha == NULL) return 0;
|
|
for (y = 0; y < pic->height; ++y) {
|
|
for (x = 0; x < pic->width; ++x) {
|
|
if (alpha[x] != 0xff) return 1;
|
|
}
|
|
alpha += pic->a_stride;
|
|
}
|
|
} else {
|
|
int x, y;
|
|
const uint32_t* argb = pic->argb;
|
|
if (argb == NULL) return 1;
|
|
for (y = 0; y < pic->height; ++y) {
|
|
for (x = 0; x < pic->width; ++x) {
|
|
if (argb[x] < 0xff000000) return 1; // test any alpha values != 0xff
|
|
}
|
|
argb += pic->argb_stride;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Distortion
|
|
|
|
// Max value returned in case of exact similarity.
|
|
static const double kMinDistortion_dB = 99.;
|
|
|
|
int WebPPictureDistortion(const WebPPicture* const pic1,
|
|
const WebPPicture* const pic2,
|
|
int type, float result[5]) {
|
|
int c;
|
|
DistoStats stats[5];
|
|
int has_alpha;
|
|
|
|
if (pic1 == NULL || pic2 == NULL ||
|
|
pic1->width != pic2->width || pic1->height != pic2->height ||
|
|
pic1->y == NULL || pic2->y == NULL ||
|
|
pic1->u == NULL || pic2->u == NULL ||
|
|
pic1->v == NULL || pic2->v == NULL ||
|
|
result == NULL) {
|
|
return 0;
|
|
}
|
|
|
|
has_alpha = !!(pic1->colorspace & WEBP_CSP_ALPHA_BIT);
|
|
if (has_alpha != !!(pic2->colorspace & WEBP_CSP_ALPHA_BIT) ||
|
|
(has_alpha && (pic1->a == NULL || pic2->a == NULL))) {
|
|
return 0;
|
|
}
|
|
|
|
memset(stats, 0, sizeof(stats));
|
|
VP8SSIMAccumulatePlane(pic1->y, pic1->y_stride,
|
|
pic2->y, pic2->y_stride,
|
|
pic1->width, pic1->height, &stats[0]);
|
|
VP8SSIMAccumulatePlane(pic1->u, pic1->uv_stride,
|
|
pic2->u, pic2->uv_stride,
|
|
(pic1->width + 1) >> 1, (pic1->height + 1) >> 1,
|
|
&stats[1]);
|
|
VP8SSIMAccumulatePlane(pic1->v, pic1->uv_stride,
|
|
pic2->v, pic2->uv_stride,
|
|
(pic1->width + 1) >> 1, (pic1->height + 1) >> 1,
|
|
&stats[2]);
|
|
if (has_alpha) {
|
|
VP8SSIMAccumulatePlane(pic1->a, pic1->a_stride,
|
|
pic2->a, pic2->a_stride,
|
|
pic1->width, pic1->height, &stats[3]);
|
|
}
|
|
for (c = 0; c <= 4; ++c) {
|
|
if (type == 1) {
|
|
const double v = VP8SSIMGet(&stats[c]);
|
|
result[c] = (float)((v < 1.) ? -10.0 * log10(1. - v)
|
|
: kMinDistortion_dB);
|
|
} else {
|
|
const double v = VP8SSIMGetSquaredError(&stats[c]);
|
|
result[c] = (float)((v > 0.) ? -4.3429448 * log(v / (255 * 255.))
|
|
: kMinDistortion_dB);
|
|
}
|
|
// Accumulate forward
|
|
if (c < 4) VP8SSIMAddStats(&stats[c], &stats[4]);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Simplest high-level calls:
|
|
|
|
typedef int (*Importer)(WebPPicture* const, const uint8_t* const, int);
|
|
|
|
static size_t Encode(const uint8_t* rgba, int width, int height, int stride,
|
|
Importer import, float quality_factor, uint8_t** output) {
|
|
size_t output_size = 0;
|
|
WebPPicture pic;
|
|
WebPConfig config;
|
|
WebPMemoryWriter wrt;
|
|
int ok;
|
|
|
|
if (!WebPConfigPreset(&config, WEBP_PRESET_DEFAULT, quality_factor) ||
|
|
!WebPPictureInit(&pic)) {
|
|
return 0; // shouldn't happen, except if system installation is broken
|
|
}
|
|
|
|
pic.width = width;
|
|
pic.height = height;
|
|
pic.writer = WebPMemoryWrite;
|
|
pic.custom_ptr = &wrt;
|
|
|
|
wrt.mem = output;
|
|
wrt.size = &output_size;
|
|
WebPMemoryWriterInit(&wrt);
|
|
|
|
ok = import(&pic, rgba, stride) && WebPEncode(&config, &pic);
|
|
WebPPictureFree(&pic);
|
|
if (!ok) {
|
|
free(*output);
|
|
*output = NULL;
|
|
return 0;
|
|
}
|
|
return output_size;
|
|
}
|
|
|
|
#define ENCODE_FUNC(NAME, IMPORTER) \
|
|
size_t NAME(const uint8_t* in, int w, int h, int bps, float q, \
|
|
uint8_t** out) { \
|
|
return Encode(in, w, h, bps, IMPORTER, q, out); \
|
|
}
|
|
|
|
ENCODE_FUNC(WebPEncodeRGB, WebPPictureImportRGB);
|
|
ENCODE_FUNC(WebPEncodeBGR, WebPPictureImportBGR);
|
|
ENCODE_FUNC(WebPEncodeRGBA, WebPPictureImportRGBA);
|
|
ENCODE_FUNC(WebPEncodeBGRA, WebPPictureImportBGRA);
|
|
|
|
#undef ENCODE_FUNC
|
|
|
|
//------------------------------------------------------------------------------
|
|
|
|
#if defined(__cplusplus) || defined(c_plusplus)
|
|
} // extern "C"
|
|
#endif
|