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-rw-r--r--media/libwebp/dec/buffer_dec.c300
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diff --git a/media/libwebp/dec/buffer_dec.c b/media/libwebp/dec/buffer_dec.c
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+// Copyright 2011 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.
+// -----------------------------------------------------------------------------
+//
+// Everything about WebPDecBuffer
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <stdlib.h>
+
+#include "./vp8i_dec.h"
+#include "./webpi_dec.h"
+#include "../utils/utils.h"
+
+//------------------------------------------------------------------------------
+// WebPDecBuffer
+
+// Number of bytes per pixel for the different color-spaces.
+static const int kModeBpp[MODE_LAST] = {
+ 3, 4, 3, 4, 4, 2, 2,
+ 4, 4, 4, 2, // pre-multiplied modes
+ 1, 1 };
+
+// Check that webp_csp_mode is within the bounds of WEBP_CSP_MODE.
+// Convert to an integer to handle both the unsigned/signed enum cases
+// without the need for casting to remove type limit warnings.
+static int IsValidColorspace(int webp_csp_mode) {
+ return (webp_csp_mode >= MODE_RGB && webp_csp_mode < MODE_LAST);
+}
+
+// strictly speaking, the very last (or first, if flipped) row
+// doesn't require padding.
+#define MIN_BUFFER_SIZE(WIDTH, HEIGHT, STRIDE) \
+ (uint64_t)(STRIDE) * ((HEIGHT) - 1) + (WIDTH)
+
+static VP8StatusCode CheckDecBuffer(const WebPDecBuffer* const buffer) {
+ int ok = 1;
+ const WEBP_CSP_MODE mode = buffer->colorspace;
+ const int width = buffer->width;
+ const int height = buffer->height;
+ if (!IsValidColorspace(mode)) {
+ ok = 0;
+ } else if (!WebPIsRGBMode(mode)) { // YUV checks
+ const WebPYUVABuffer* const buf = &buffer->u.YUVA;
+ const int uv_width = (width + 1) / 2;
+ const int uv_height = (height + 1) / 2;
+ const int y_stride = abs(buf->y_stride);
+ const int u_stride = abs(buf->u_stride);
+ const int v_stride = abs(buf->v_stride);
+ const int a_stride = abs(buf->a_stride);
+ const uint64_t y_size = MIN_BUFFER_SIZE(width, height, y_stride);
+ const uint64_t u_size = MIN_BUFFER_SIZE(uv_width, uv_height, u_stride);
+ const uint64_t v_size = MIN_BUFFER_SIZE(uv_width, uv_height, v_stride);
+ const uint64_t a_size = MIN_BUFFER_SIZE(width, height, a_stride);
+ ok &= (y_size <= buf->y_size);
+ ok &= (u_size <= buf->u_size);
+ ok &= (v_size <= buf->v_size);
+ ok &= (y_stride >= width);
+ ok &= (u_stride >= uv_width);
+ ok &= (v_stride >= uv_width);
+ ok &= (buf->y != NULL);
+ ok &= (buf->u != NULL);
+ ok &= (buf->v != NULL);
+ if (mode == MODE_YUVA) {
+ ok &= (a_stride >= width);
+ ok &= (a_size <= buf->a_size);
+ ok &= (buf->a != NULL);
+ }
+ } else { // RGB checks
+ const WebPRGBABuffer* const buf = &buffer->u.RGBA;
+ const int stride = abs(buf->stride);
+ const uint64_t size = MIN_BUFFER_SIZE(width, height, stride);
+ ok &= (size <= buf->size);
+ ok &= (stride >= width * kModeBpp[mode]);
+ ok &= (buf->rgba != NULL);
+ }
+ return ok ? VP8_STATUS_OK : VP8_STATUS_INVALID_PARAM;
+}
+#undef MIN_BUFFER_SIZE
+
+static VP8StatusCode AllocateBuffer(WebPDecBuffer* const buffer) {
+ const int w = buffer->width;
+ const int h = buffer->height;
+ const WEBP_CSP_MODE mode = buffer->colorspace;
+
+ if (w <= 0 || h <= 0 || !IsValidColorspace(mode)) {
+ return VP8_STATUS_INVALID_PARAM;
+ }
+
+ if (buffer->is_external_memory <= 0 && buffer->private_memory == NULL) {
+ uint8_t* output;
+ int uv_stride = 0, a_stride = 0;
+ uint64_t uv_size = 0, a_size = 0, total_size;
+ // We need memory and it hasn't been allocated yet.
+ // => initialize output buffer, now that dimensions are known.
+ const int stride = w * kModeBpp[mode];
+ const uint64_t size = (uint64_t)stride * h;
+
+ if (!WebPIsRGBMode(mode)) {
+ uv_stride = (w + 1) / 2;
+ uv_size = (uint64_t)uv_stride * ((h + 1) / 2);
+ if (mode == MODE_YUVA) {
+ a_stride = w;
+ a_size = (uint64_t)a_stride * h;
+ }
+ }
+ total_size = size + 2 * uv_size + a_size;
+
+ // Security/sanity checks
+ output = (uint8_t*)WebPSafeMalloc(total_size, sizeof(*output));
+ if (output == NULL) {
+ return VP8_STATUS_OUT_OF_MEMORY;
+ }
+ buffer->private_memory = output;
+
+ if (!WebPIsRGBMode(mode)) { // YUVA initialization
+ WebPYUVABuffer* const buf = &buffer->u.YUVA;
+ buf->y = output;
+ buf->y_stride = stride;
+ buf->y_size = (size_t)size;
+ buf->u = output + size;
+ buf->u_stride = uv_stride;
+ buf->u_size = (size_t)uv_size;
+ buf->v = output + size + uv_size;
+ buf->v_stride = uv_stride;
+ buf->v_size = (size_t)uv_size;
+ if (mode == MODE_YUVA) {
+ buf->a = output + size + 2 * uv_size;
+ }
+ buf->a_size = (size_t)a_size;
+ buf->a_stride = a_stride;
+ } else { // RGBA initialization
+ WebPRGBABuffer* const buf = &buffer->u.RGBA;
+ buf->rgba = output;
+ buf->stride = stride;
+ buf->size = (size_t)size;
+ }
+ }
+ return CheckDecBuffer(buffer);
+}
+
+VP8StatusCode WebPFlipBuffer(WebPDecBuffer* const buffer) {
+ if (buffer == NULL) {
+ return VP8_STATUS_INVALID_PARAM;
+ }
+ if (WebPIsRGBMode(buffer->colorspace)) {
+ WebPRGBABuffer* const buf = &buffer->u.RGBA;
+ buf->rgba += (buffer->height - 1) * buf->stride;
+ buf->stride = -buf->stride;
+ } else {
+ WebPYUVABuffer* const buf = &buffer->u.YUVA;
+ const int H = buffer->height;
+ buf->y += (H - 1) * buf->y_stride;
+ buf->y_stride = -buf->y_stride;
+ buf->u += ((H - 1) >> 1) * buf->u_stride;
+ buf->u_stride = -buf->u_stride;
+ buf->v += ((H - 1) >> 1) * buf->v_stride;
+ buf->v_stride = -buf->v_stride;
+ if (buf->a != NULL) {
+ buf->a += (H - 1) * buf->a_stride;
+ buf->a_stride = -buf->a_stride;
+ }
+ }
+ return VP8_STATUS_OK;
+}
+
+VP8StatusCode WebPAllocateDecBuffer(int w, int h,
+ const WebPDecoderOptions* const options,
+ WebPDecBuffer* const out) {
+ VP8StatusCode status;
+ if (out == NULL || w <= 0 || h <= 0) {
+ return VP8_STATUS_INVALID_PARAM;
+ }
+ if (options != NULL) { // First, apply options if there is any.
+ if (options->use_cropping) {
+ const int cw = options->crop_width;
+ const int ch = options->crop_height;
+ const int x = options->crop_left & ~1;
+ const int y = options->crop_top & ~1;
+ if (x < 0 || y < 0 || cw <= 0 || ch <= 0 || x + cw > w || y + ch > h) {
+ return VP8_STATUS_INVALID_PARAM; // out of frame boundary.
+ }
+ w = cw;
+ h = ch;
+ }
+ if (options->use_scaling) {
+ int scaled_width = options->scaled_width;
+ int scaled_height = options->scaled_height;
+ if (!WebPRescalerGetScaledDimensions(
+ w, h, &scaled_width, &scaled_height)) {
+ return VP8_STATUS_INVALID_PARAM;
+ }
+ w = scaled_width;
+ h = scaled_height;
+ }
+ }
+ out->width = w;
+ out->height = h;
+
+ // Then, allocate buffer for real.
+ status = AllocateBuffer(out);
+ if (status != VP8_STATUS_OK) return status;
+
+ // Use the stride trick if vertical flip is needed.
+ if (options != NULL && options->flip) {
+ status = WebPFlipBuffer(out);
+ }
+ return status;
+}
+
+//------------------------------------------------------------------------------
+// constructors / destructors
+
+int WebPInitDecBufferInternal(WebPDecBuffer* buffer, int version) {
+ if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) {
+ return 0; // version mismatch
+ }
+ if (buffer == NULL) return 0;
+ memset(buffer, 0, sizeof(*buffer));
+ return 1;
+}
+
+void WebPFreeDecBuffer(WebPDecBuffer* buffer) {
+ if (buffer != NULL) {
+ if (buffer->is_external_memory <= 0) {
+ WebPSafeFree(buffer->private_memory);
+ }
+ buffer->private_memory = NULL;
+ }
+}
+
+void WebPCopyDecBuffer(const WebPDecBuffer* const src,
+ WebPDecBuffer* const dst) {
+ if (src != NULL && dst != NULL) {
+ *dst = *src;
+ if (src->private_memory != NULL) {
+ dst->is_external_memory = 1; // dst buffer doesn't own the memory.
+ dst->private_memory = NULL;
+ }
+ }
+}
+
+// Copy and transfer ownership from src to dst (beware of parameter order!)
+void WebPGrabDecBuffer(WebPDecBuffer* const src, WebPDecBuffer* const dst) {
+ if (src != NULL && dst != NULL) {
+ *dst = *src;
+ if (src->private_memory != NULL) {
+ src->is_external_memory = 1; // src relinquishes ownership
+ src->private_memory = NULL;
+ }
+ }
+}
+
+VP8StatusCode WebPCopyDecBufferPixels(const WebPDecBuffer* const src_buf,
+ WebPDecBuffer* const dst_buf) {
+ assert(src_buf != NULL && dst_buf != NULL);
+ assert(src_buf->colorspace == dst_buf->colorspace);
+
+ dst_buf->width = src_buf->width;
+ dst_buf->height = src_buf->height;
+ if (CheckDecBuffer(dst_buf) != VP8_STATUS_OK) {
+ return VP8_STATUS_INVALID_PARAM;
+ }
+ if (WebPIsRGBMode(src_buf->colorspace)) {
+ const WebPRGBABuffer* const src = &src_buf->u.RGBA;
+ const WebPRGBABuffer* const dst = &dst_buf->u.RGBA;
+ WebPCopyPlane(src->rgba, src->stride, dst->rgba, dst->stride,
+ src_buf->width * kModeBpp[src_buf->colorspace],
+ src_buf->height);
+ } else {
+ const WebPYUVABuffer* const src = &src_buf->u.YUVA;
+ const WebPYUVABuffer* const dst = &dst_buf->u.YUVA;
+ WebPCopyPlane(src->y, src->y_stride, dst->y, dst->y_stride,
+ src_buf->width, src_buf->height);
+ WebPCopyPlane(src->u, src->u_stride, dst->u, dst->u_stride,
+ (src_buf->width + 1) / 2, (src_buf->height + 1) / 2);
+ WebPCopyPlane(src->v, src->v_stride, dst->v, dst->v_stride,
+ (src_buf->width + 1) / 2, (src_buf->height + 1) / 2);
+ if (WebPIsAlphaMode(src_buf->colorspace)) {
+ WebPCopyPlane(src->a, src->a_stride, dst->a, dst->a_stride,
+ src_buf->width, src_buf->height);
+ }
+ }
+ return VP8_STATUS_OK;
+}
+
+int WebPAvoidSlowMemory(const WebPDecBuffer* const output,
+ const WebPBitstreamFeatures* const features) {
+ assert(output != NULL);
+ return (output->is_external_memory >= 2) &&
+ WebPIsPremultipliedMode(output->colorspace) &&
+ (features != NULL && features->has_alpha);
+}
+
+//------------------------------------------------------------------------------