third_party/libwebp/src/dec/buffer_dec.c - cobalt - Git at Google

 // 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)

 #if defined(STARBOARD)
 #include "starboard/client_porting/poem/assert_poem.h"
 #include "starboard/client_porting/poem/string_poem.h"
 #endif

 #include <stdlib.h>

 #include "src/dec/vp8i_dec.h"
 #include "src/dec/webpi_dec.h"
 #include "src/utils/utils.h"

 //------------------------------------------------------------------------------
 // WebPDecBuffer

 // Number of bytes per pixel for the different color-spaces.
 static const uint8_t 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.
     int stride;
     uint64_t size;

     if ((uint64_t)w * kModeBpp[mode] >= (1ull << 32)) {
       return VP8_STATUS_INVALID_PARAM;
     }
     stride = w * kModeBpp[mode];
     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 width, int height,
                                     const WebPDecoderOptions* const options,
                                     WebPDecBuffer* const buffer) {
   VP8StatusCode status;
   if (buffer == NULL || width <= 0 || height <= 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 > width || y + ch > height) {
         return VP8_STATUS_INVALID_PARAM;   // out of frame boundary.
       }
       width = cw;
       height = ch;
     }

     if (options->use_scaling) {
 #if !defined(WEBP_REDUCE_SIZE)
       int scaled_width = options->scaled_width;
       int scaled_height = options->scaled_height;
       if (!WebPRescalerGetScaledDimensions(
               width, height, &scaled_width, &scaled_height)) {
         return VP8_STATUS_INVALID_PARAM;
       }
       width = scaled_width;
       height = scaled_height;
 #else
       return VP8_STATUS_INVALID_PARAM;   // rescaling not supported
 #endif
     }
   }
   buffer->width = width;
   buffer->height = height;

   // Then, allocate buffer for real.
   status = AllocateBuffer(buffer);
   if (status != VP8_STATUS_OK) return status;

   // Use the stride trick if vertical flip is needed.
   if (options != NULL && options->flip) {
     status = WebPFlipBuffer(buffer);
   }
   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);
 }

 //------------------------------------------------------------------------------
	// 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)

	#if defined(STARBOARD)
	#include "starboard/client_porting/poem/assert_poem.h"
	#include "starboard/client_porting/poem/string_poem.h"
	#endif

	#include <stdlib.h>

	#include "src/dec/vp8i_dec.h"
	#include "src/dec/webpi_dec.h"
	#include "src/utils/utils.h"

	//------------------------------------------------------------------------------
	// WebPDecBuffer

	// Number of bytes per pixel for the different color-spaces.
	static const uint8_t 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.
	int stride;
	uint64_t size;

	if ((uint64_t)w * kModeBpp[mode] >= (1ull << 32)) {
	return VP8_STATUS_INVALID_PARAM;
	}
	stride = w * kModeBpp[mode];
	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 width, int height,
	const WebPDecoderOptions* const options,
	WebPDecBuffer* const buffer) {
	VP8StatusCode status;
	if (buffer == NULL \|\| width <= 0 \|\| height <= 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 > width \|\| y + ch > height) {
	return VP8_STATUS_INVALID_PARAM; // out of frame boundary.
	}
	width = cw;
	height = ch;
	}

	if (options->use_scaling) {
	#if !defined(WEBP_REDUCE_SIZE)
	int scaled_width = options->scaled_width;
	int scaled_height = options->scaled_height;
	if (!WebPRescalerGetScaledDimensions(
	width, height, &scaled_width, &scaled_height)) {
	return VP8_STATUS_INVALID_PARAM;
	}
	width = scaled_width;
	height = scaled_height;
	#else
	return VP8_STATUS_INVALID_PARAM; // rescaling not supported
	#endif
	}
	}
	buffer->width = width;
	buffer->height = height;

	// Then, allocate buffer for real.
	status = AllocateBuffer(buffer);
	if (status != VP8_STATUS_OK) return status;

	// Use the stride trick if vertical flip is needed.
	if (options != NULL && options->flip) {
	status = WebPFlipBuffer(buffer);
	}
	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);
	}

	//------------------------------------------------------------------------------