diff options
author | volzhs <volzhs@gmail.com> | 2017-02-17 23:49:40 +0900 |
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committer | volzhs <volzhs@gmail.com> | 2017-02-17 23:49:40 +0900 |
commit | 6de3defe7271441f6e55e1a0ed5e115a92a72606 (patch) | |
tree | 70cbb89a4a91a6f4731a4cbfc2792b56c86dddbe /thirdparty/libwebp/dec/webp.c | |
parent | 903a3aa5f0e128abb1fb752c10b343b34af8f799 (diff) |
Update libwebp to 0.6.0
Diffstat (limited to 'thirdparty/libwebp/dec/webp.c')
-rw-r--r-- | thirdparty/libwebp/dec/webp.c | 846 |
1 files changed, 0 insertions, 846 deletions
diff --git a/thirdparty/libwebp/dec/webp.c b/thirdparty/libwebp/dec/webp.c deleted file mode 100644 index d0b912f02f..0000000000 --- a/thirdparty/libwebp/dec/webp.c +++ /dev/null @@ -1,846 +0,0 @@ -// Copyright 2010 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. -// ----------------------------------------------------------------------------- -// -// Main decoding functions for WEBP images. -// -// Author: Skal (pascal.massimino@gmail.com) - -#include <stdlib.h> - -#include "./vp8i.h" -#include "./vp8li.h" -#include "./webpi.h" -#include "../utils/utils.h" -#include "../webp/mux_types.h" // ALPHA_FLAG - -//------------------------------------------------------------------------------ -// RIFF layout is: -// Offset 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 -// The RIFF container (12 bytes) is followed by appropriate chunks: -// 12..15 "VP8 ": 4-bytes tags, signaling the use of VP8 video format -// 16..19 size of the raw VP8 image data, starting at offset 20 -// 20.... the VP8 bytes -// Or, -// 12..15 "VP8L": 4-bytes tags, signaling the use of VP8L lossless format -// 16..19 size of the raw VP8L image data, starting at offset 20 -// 20.... the VP8L bytes -// Or, -// 12..15 "VP8X": 4-bytes tags, describing the extended-VP8 chunk. -// 16..19 size of the VP8X chunk starting at offset 20. -// 20..23 VP8X flags bit-map corresponding to the chunk-types present. -// 24..26 Width of the Canvas Image. -// 27..29 Height of the Canvas Image. -// There can be extra chunks after the "VP8X" chunk (ICCP, FRGM, ANMF, VP8, -// VP8L, XMP, EXIF ...) -// All sizes are in little-endian order. -// Note: chunk data size must be padded to multiple of 2 when written. - -// Validates the RIFF container (if detected) and skips over it. -// If a RIFF container is detected, returns: -// VP8_STATUS_BITSTREAM_ERROR for invalid header, -// VP8_STATUS_NOT_ENOUGH_DATA for truncated data if have_all_data is true, -// and VP8_STATUS_OK otherwise. -// In case there are not enough bytes (partial RIFF container), return 0 for -// *riff_size. Else return the RIFF size extracted from the header. -static VP8StatusCode ParseRIFF(const uint8_t** const data, - size_t* const data_size, int have_all_data, - size_t* const riff_size) { - assert(data != NULL); - assert(data_size != NULL); - assert(riff_size != NULL); - - *riff_size = 0; // Default: no RIFF present. - if (*data_size >= RIFF_HEADER_SIZE && !memcmp(*data, "RIFF", TAG_SIZE)) { - if (memcmp(*data + 8, "WEBP", TAG_SIZE)) { - return VP8_STATUS_BITSTREAM_ERROR; // Wrong image file signature. - } else { - const uint32_t size = GetLE32(*data + TAG_SIZE); - // Check that we have at least one chunk (i.e "WEBP" + "VP8?nnnn"). - if (size < TAG_SIZE + CHUNK_HEADER_SIZE) { - return VP8_STATUS_BITSTREAM_ERROR; - } - if (size > MAX_CHUNK_PAYLOAD) { - return VP8_STATUS_BITSTREAM_ERROR; - } - if (have_all_data && (size > *data_size - CHUNK_HEADER_SIZE)) { - return VP8_STATUS_NOT_ENOUGH_DATA; // Truncated bitstream. - } - // We have a RIFF container. Skip it. - *riff_size = size; - *data += RIFF_HEADER_SIZE; - *data_size -= RIFF_HEADER_SIZE; - } - } - return VP8_STATUS_OK; -} - -// Validates the VP8X header and skips over it. -// Returns VP8_STATUS_BITSTREAM_ERROR for invalid VP8X header, -// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and -// VP8_STATUS_OK otherwise. -// If a VP8X chunk is found, found_vp8x is set to true and *width_ptr, -// *height_ptr and *flags_ptr are set to the corresponding values extracted -// from the VP8X chunk. -static VP8StatusCode ParseVP8X(const uint8_t** const data, - size_t* const data_size, - int* const found_vp8x, - int* const width_ptr, int* const height_ptr, - uint32_t* const flags_ptr) { - const uint32_t vp8x_size = CHUNK_HEADER_SIZE + VP8X_CHUNK_SIZE; - assert(data != NULL); - assert(data_size != NULL); - assert(found_vp8x != NULL); - - *found_vp8x = 0; - - if (*data_size < CHUNK_HEADER_SIZE) { - return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. - } - - if (!memcmp(*data, "VP8X", TAG_SIZE)) { - int width, height; - uint32_t flags; - const uint32_t chunk_size = GetLE32(*data + TAG_SIZE); - if (chunk_size != VP8X_CHUNK_SIZE) { - return VP8_STATUS_BITSTREAM_ERROR; // Wrong chunk size. - } - - // Verify if enough data is available to validate the VP8X chunk. - if (*data_size < vp8x_size) { - return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. - } - flags = GetLE32(*data + 8); - width = 1 + GetLE24(*data + 12); - height = 1 + GetLE24(*data + 15); - if (width * (uint64_t)height >= MAX_IMAGE_AREA) { - return VP8_STATUS_BITSTREAM_ERROR; // image is too large - } - - if (flags_ptr != NULL) *flags_ptr = flags; - if (width_ptr != NULL) *width_ptr = width; - if (height_ptr != NULL) *height_ptr = height; - // Skip over VP8X header bytes. - *data += vp8x_size; - *data_size -= vp8x_size; - *found_vp8x = 1; - } - return VP8_STATUS_OK; -} - -// Skips to the next VP8/VP8L chunk header in the data given the size of the -// RIFF chunk 'riff_size'. -// Returns VP8_STATUS_BITSTREAM_ERROR if any invalid chunk size is encountered, -// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and -// VP8_STATUS_OK otherwise. -// If an alpha chunk is found, *alpha_data and *alpha_size are set -// appropriately. -static VP8StatusCode ParseOptionalChunks(const uint8_t** const data, - size_t* const data_size, - size_t const riff_size, - const uint8_t** const alpha_data, - size_t* const alpha_size) { - const uint8_t* buf; - size_t buf_size; - uint32_t total_size = TAG_SIZE + // "WEBP". - CHUNK_HEADER_SIZE + // "VP8Xnnnn". - VP8X_CHUNK_SIZE; // data. - assert(data != NULL); - assert(data_size != NULL); - buf = *data; - buf_size = *data_size; - - assert(alpha_data != NULL); - assert(alpha_size != NULL); - *alpha_data = NULL; - *alpha_size = 0; - - while (1) { - uint32_t chunk_size; - uint32_t disk_chunk_size; // chunk_size with padding - - *data = buf; - *data_size = buf_size; - - if (buf_size < CHUNK_HEADER_SIZE) { // Insufficient data. - return VP8_STATUS_NOT_ENOUGH_DATA; - } - - chunk_size = GetLE32(buf + TAG_SIZE); - if (chunk_size > MAX_CHUNK_PAYLOAD) { - return VP8_STATUS_BITSTREAM_ERROR; // Not a valid chunk size. - } - // For odd-sized chunk-payload, there's one byte padding at the end. - disk_chunk_size = (CHUNK_HEADER_SIZE + chunk_size + 1) & ~1; - total_size += disk_chunk_size; - - // Check that total bytes skipped so far does not exceed riff_size. - if (riff_size > 0 && (total_size > riff_size)) { - return VP8_STATUS_BITSTREAM_ERROR; // Not a valid chunk size. - } - - // Start of a (possibly incomplete) VP8/VP8L chunk implies that we have - // parsed all the optional chunks. - // Note: This check must occur before the check 'buf_size < disk_chunk_size' - // below to allow incomplete VP8/VP8L chunks. - if (!memcmp(buf, "VP8 ", TAG_SIZE) || - !memcmp(buf, "VP8L", TAG_SIZE)) { - return VP8_STATUS_OK; - } - - if (buf_size < disk_chunk_size) { // Insufficient data. - return VP8_STATUS_NOT_ENOUGH_DATA; - } - - if (!memcmp(buf, "ALPH", TAG_SIZE)) { // A valid ALPH header. - *alpha_data = buf + CHUNK_HEADER_SIZE; - *alpha_size = chunk_size; - } - - // We have a full and valid chunk; skip it. - buf += disk_chunk_size; - buf_size -= disk_chunk_size; - } -} - -// Validates the VP8/VP8L Header ("VP8 nnnn" or "VP8L nnnn") and skips over it. -// Returns VP8_STATUS_BITSTREAM_ERROR for invalid (chunk larger than -// riff_size) VP8/VP8L header, -// VP8_STATUS_NOT_ENOUGH_DATA in case of insufficient data, and -// VP8_STATUS_OK otherwise. -// If a VP8/VP8L chunk is found, *chunk_size is set to the total number of bytes -// extracted from the VP8/VP8L chunk header. -// The flag '*is_lossless' is set to 1 in case of VP8L chunk / raw VP8L data. -static VP8StatusCode ParseVP8Header(const uint8_t** const data_ptr, - size_t* const data_size, int have_all_data, - size_t riff_size, size_t* const chunk_size, - int* const is_lossless) { - const uint8_t* const data = *data_ptr; - const int is_vp8 = !memcmp(data, "VP8 ", TAG_SIZE); - const int is_vp8l = !memcmp(data, "VP8L", TAG_SIZE); - const uint32_t minimal_size = - TAG_SIZE + CHUNK_HEADER_SIZE; // "WEBP" + "VP8 nnnn" OR - // "WEBP" + "VP8Lnnnn" - assert(data != NULL); - assert(data_size != NULL); - assert(chunk_size != NULL); - assert(is_lossless != NULL); - - if (*data_size < CHUNK_HEADER_SIZE) { - return VP8_STATUS_NOT_ENOUGH_DATA; // Insufficient data. - } - - if (is_vp8 || is_vp8l) { - // Bitstream contains VP8/VP8L header. - const uint32_t size = GetLE32(data + TAG_SIZE); - if ((riff_size >= minimal_size) && (size > riff_size - minimal_size)) { - return VP8_STATUS_BITSTREAM_ERROR; // Inconsistent size information. - } - if (have_all_data && (size > *data_size - CHUNK_HEADER_SIZE)) { - return VP8_STATUS_NOT_ENOUGH_DATA; // Truncated bitstream. - } - // Skip over CHUNK_HEADER_SIZE bytes from VP8/VP8L Header. - *chunk_size = size; - *data_ptr += CHUNK_HEADER_SIZE; - *data_size -= CHUNK_HEADER_SIZE; - *is_lossless = is_vp8l; - } else { - // Raw VP8/VP8L bitstream (no header). - *is_lossless = VP8LCheckSignature(data, *data_size); - *chunk_size = *data_size; - } - - return VP8_STATUS_OK; -} - -//------------------------------------------------------------------------------ - -// Fetch '*width', '*height', '*has_alpha' and fill out 'headers' based on -// 'data'. All the output parameters may be NULL. If 'headers' is NULL only the -// minimal amount will be read to fetch the remaining parameters. -// If 'headers' is non-NULL this function will attempt to locate both alpha -// data (with or without a VP8X chunk) and the bitstream chunk (VP8/VP8L). -// Note: The following chunk sequences (before the raw VP8/VP8L data) are -// considered valid by this function: -// RIFF + VP8(L) -// RIFF + VP8X + (optional chunks) + VP8(L) -// ALPH + VP8 <-- Not a valid WebP format: only allowed for internal purpose. -// VP8(L) <-- Not a valid WebP format: only allowed for internal purpose. -static VP8StatusCode ParseHeadersInternal(const uint8_t* data, - size_t data_size, - int* const width, - int* const height, - int* const has_alpha, - int* const has_animation, - int* const format, - WebPHeaderStructure* const headers) { - int canvas_width = 0; - int canvas_height = 0; - int image_width = 0; - int image_height = 0; - int found_riff = 0; - int found_vp8x = 0; - int animation_present = 0; - int fragments_present = 0; - const int have_all_data = (headers != NULL) ? headers->have_all_data : 0; - - VP8StatusCode status; - WebPHeaderStructure hdrs; - - if (data == NULL || data_size < RIFF_HEADER_SIZE) { - return VP8_STATUS_NOT_ENOUGH_DATA; - } - memset(&hdrs, 0, sizeof(hdrs)); - hdrs.data = data; - hdrs.data_size = data_size; - - // Skip over RIFF header. - status = ParseRIFF(&data, &data_size, have_all_data, &hdrs.riff_size); - if (status != VP8_STATUS_OK) { - return status; // Wrong RIFF header / insufficient data. - } - found_riff = (hdrs.riff_size > 0); - - // Skip over VP8X. - { - uint32_t flags = 0; - status = ParseVP8X(&data, &data_size, &found_vp8x, - &canvas_width, &canvas_height, &flags); - if (status != VP8_STATUS_OK) { - return status; // Wrong VP8X / insufficient data. - } - animation_present = !!(flags & ANIMATION_FLAG); - fragments_present = !!(flags & FRAGMENTS_FLAG); - if (!found_riff && found_vp8x) { - // Note: This restriction may be removed in the future, if it becomes - // necessary to send VP8X chunk to the decoder. - return VP8_STATUS_BITSTREAM_ERROR; - } - if (has_alpha != NULL) *has_alpha = !!(flags & ALPHA_FLAG); - if (has_animation != NULL) *has_animation = animation_present; - if (format != NULL) *format = 0; // default = undefined - - image_width = canvas_width; - image_height = canvas_height; - if (found_vp8x && (animation_present || fragments_present) && - headers == NULL) { - status = VP8_STATUS_OK; - goto ReturnWidthHeight; // Just return features from VP8X header. - } - } - - if (data_size < TAG_SIZE) { - status = VP8_STATUS_NOT_ENOUGH_DATA; - goto ReturnWidthHeight; - } - - // Skip over optional chunks if data started with "RIFF + VP8X" or "ALPH". - if ((found_riff && found_vp8x) || - (!found_riff && !found_vp8x && !memcmp(data, "ALPH", TAG_SIZE))) { - status = ParseOptionalChunks(&data, &data_size, hdrs.riff_size, - &hdrs.alpha_data, &hdrs.alpha_data_size); - if (status != VP8_STATUS_OK) { - goto ReturnWidthHeight; // Invalid chunk size / insufficient data. - } - } - - // Skip over VP8/VP8L header. - status = ParseVP8Header(&data, &data_size, have_all_data, hdrs.riff_size, - &hdrs.compressed_size, &hdrs.is_lossless); - if (status != VP8_STATUS_OK) { - goto ReturnWidthHeight; // Wrong VP8/VP8L chunk-header / insufficient data. - } - if (hdrs.compressed_size > MAX_CHUNK_PAYLOAD) { - return VP8_STATUS_BITSTREAM_ERROR; - } - - if (format != NULL && !(animation_present || fragments_present)) { - *format = hdrs.is_lossless ? 2 : 1; - } - - if (!hdrs.is_lossless) { - if (data_size < VP8_FRAME_HEADER_SIZE) { - status = VP8_STATUS_NOT_ENOUGH_DATA; - goto ReturnWidthHeight; - } - // Validates raw VP8 data. - if (!VP8GetInfo(data, data_size, (uint32_t)hdrs.compressed_size, - &image_width, &image_height)) { - return VP8_STATUS_BITSTREAM_ERROR; - } - } else { - if (data_size < VP8L_FRAME_HEADER_SIZE) { - status = VP8_STATUS_NOT_ENOUGH_DATA; - goto ReturnWidthHeight; - } - // Validates raw VP8L data. - if (!VP8LGetInfo(data, data_size, &image_width, &image_height, has_alpha)) { - return VP8_STATUS_BITSTREAM_ERROR; - } - } - // Validates image size coherency. - if (found_vp8x) { - if (canvas_width != image_width || canvas_height != image_height) { - return VP8_STATUS_BITSTREAM_ERROR; - } - } - if (headers != NULL) { - *headers = hdrs; - headers->offset = data - headers->data; - assert((uint64_t)(data - headers->data) < MAX_CHUNK_PAYLOAD); - assert(headers->offset == headers->data_size - data_size); - } - ReturnWidthHeight: - if (status == VP8_STATUS_OK || - (status == VP8_STATUS_NOT_ENOUGH_DATA && found_vp8x && headers == NULL)) { - if (has_alpha != NULL) { - // If the data did not contain a VP8X/VP8L chunk the only definitive way - // to set this is by looking for alpha data (from an ALPH chunk). - *has_alpha |= (hdrs.alpha_data != NULL); - } - if (width != NULL) *width = image_width; - if (height != NULL) *height = image_height; - return VP8_STATUS_OK; - } else { - return status; - } -} - -VP8StatusCode WebPParseHeaders(WebPHeaderStructure* const headers) { - // status is marked volatile as a workaround for a clang-3.8 (aarch64) bug - volatile VP8StatusCode status; - int has_animation = 0; - assert(headers != NULL); - // fill out headers, ignore width/height/has_alpha. - status = ParseHeadersInternal(headers->data, headers->data_size, - NULL, NULL, NULL, &has_animation, - NULL, headers); - if (status == VP8_STATUS_OK || status == VP8_STATUS_NOT_ENOUGH_DATA) { - // TODO(jzern): full support of animation frames will require API additions. - if (has_animation) { - status = VP8_STATUS_UNSUPPORTED_FEATURE; - } - } - return status; -} - -//------------------------------------------------------------------------------ -// WebPDecParams - -void WebPResetDecParams(WebPDecParams* const params) { - if (params != NULL) { - memset(params, 0, sizeof(*params)); - } -} - -//------------------------------------------------------------------------------ -// "Into" decoding variants - -// Main flow -static VP8StatusCode DecodeInto(const uint8_t* const data, size_t data_size, - WebPDecParams* const params) { - VP8StatusCode status; - VP8Io io; - WebPHeaderStructure headers; - - headers.data = data; - headers.data_size = data_size; - headers.have_all_data = 1; - status = WebPParseHeaders(&headers); // Process Pre-VP8 chunks. - if (status != VP8_STATUS_OK) { - return status; - } - - assert(params != NULL); - VP8InitIo(&io); - io.data = headers.data + headers.offset; - io.data_size = headers.data_size - headers.offset; - WebPInitCustomIo(params, &io); // Plug the I/O functions. - - if (!headers.is_lossless) { - VP8Decoder* const dec = VP8New(); - if (dec == NULL) { - return VP8_STATUS_OUT_OF_MEMORY; - } - dec->alpha_data_ = headers.alpha_data; - dec->alpha_data_size_ = headers.alpha_data_size; - - // Decode bitstream header, update io->width/io->height. - if (!VP8GetHeaders(dec, &io)) { - status = dec->status_; // An error occurred. Grab error status. - } else { - // Allocate/check output buffers. - status = WebPAllocateDecBuffer(io.width, io.height, params->options, - params->output); - if (status == VP8_STATUS_OK) { // Decode - // This change must be done before calling VP8Decode() - dec->mt_method_ = VP8GetThreadMethod(params->options, &headers, - io.width, io.height); - VP8InitDithering(params->options, dec); - if (!VP8Decode(dec, &io)) { - status = dec->status_; - } - } - } - VP8Delete(dec); - } else { - VP8LDecoder* const dec = VP8LNew(); - if (dec == NULL) { - return VP8_STATUS_OUT_OF_MEMORY; - } - if (!VP8LDecodeHeader(dec, &io)) { - status = dec->status_; // An error occurred. Grab error status. - } else { - // Allocate/check output buffers. - status = WebPAllocateDecBuffer(io.width, io.height, params->options, - params->output); - if (status == VP8_STATUS_OK) { // Decode - if (!VP8LDecodeImage(dec)) { - status = dec->status_; - } - } - } - VP8LDelete(dec); - } - - if (status != VP8_STATUS_OK) { - WebPFreeDecBuffer(params->output); - } else { - if (params->options != NULL && params->options->flip) { - // This restores the original stride values if options->flip was used - // during the call to WebPAllocateDecBuffer above. - status = WebPFlipBuffer(params->output); - } - } - return status; -} - -// Helpers -static uint8_t* DecodeIntoRGBABuffer(WEBP_CSP_MODE colorspace, - const uint8_t* const data, - size_t data_size, - uint8_t* const rgba, - int stride, size_t size) { - WebPDecParams params; - WebPDecBuffer buf; - if (rgba == NULL) { - return NULL; - } - WebPInitDecBuffer(&buf); - WebPResetDecParams(¶ms); - params.output = &buf; - buf.colorspace = colorspace; - buf.u.RGBA.rgba = rgba; - buf.u.RGBA.stride = stride; - buf.u.RGBA.size = size; - buf.is_external_memory = 1; - if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { - return NULL; - } - return rgba; -} - -uint8_t* WebPDecodeRGBInto(const uint8_t* data, size_t data_size, - uint8_t* output, size_t size, int stride) { - return DecodeIntoRGBABuffer(MODE_RGB, data, data_size, output, stride, size); -} - -uint8_t* WebPDecodeRGBAInto(const uint8_t* data, size_t data_size, - uint8_t* output, size_t size, int stride) { - return DecodeIntoRGBABuffer(MODE_RGBA, data, data_size, output, stride, size); -} - -uint8_t* WebPDecodeARGBInto(const uint8_t* data, size_t data_size, - uint8_t* output, size_t size, int stride) { - return DecodeIntoRGBABuffer(MODE_ARGB, data, data_size, output, stride, size); -} - -uint8_t* WebPDecodeBGRInto(const uint8_t* data, size_t data_size, - uint8_t* output, size_t size, int stride) { - return DecodeIntoRGBABuffer(MODE_BGR, data, data_size, output, stride, size); -} - -uint8_t* WebPDecodeBGRAInto(const uint8_t* data, size_t data_size, - uint8_t* output, size_t size, int stride) { - return DecodeIntoRGBABuffer(MODE_BGRA, data, data_size, output, stride, size); -} - -uint8_t* WebPDecodeYUVInto(const uint8_t* data, size_t data_size, - uint8_t* luma, size_t luma_size, int luma_stride, - uint8_t* u, size_t u_size, int u_stride, - uint8_t* v, size_t v_size, int v_stride) { - WebPDecParams params; - WebPDecBuffer output; - if (luma == NULL) return NULL; - WebPInitDecBuffer(&output); - WebPResetDecParams(¶ms); - params.output = &output; - output.colorspace = MODE_YUV; - output.u.YUVA.y = luma; - output.u.YUVA.y_stride = luma_stride; - output.u.YUVA.y_size = luma_size; - output.u.YUVA.u = u; - output.u.YUVA.u_stride = u_stride; - output.u.YUVA.u_size = u_size; - output.u.YUVA.v = v; - output.u.YUVA.v_stride = v_stride; - output.u.YUVA.v_size = v_size; - output.is_external_memory = 1; - if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { - return NULL; - } - return luma; -} - -//------------------------------------------------------------------------------ - -static uint8_t* Decode(WEBP_CSP_MODE mode, const uint8_t* const data, - size_t data_size, int* const width, int* const height, - WebPDecBuffer* const keep_info) { - WebPDecParams params; - WebPDecBuffer output; - - WebPInitDecBuffer(&output); - WebPResetDecParams(¶ms); - params.output = &output; - output.colorspace = mode; - - // Retrieve (and report back) the required dimensions from bitstream. - if (!WebPGetInfo(data, data_size, &output.width, &output.height)) { - return NULL; - } - if (width != NULL) *width = output.width; - if (height != NULL) *height = output.height; - - // Decode - if (DecodeInto(data, data_size, ¶ms) != VP8_STATUS_OK) { - return NULL; - } - if (keep_info != NULL) { // keep track of the side-info - WebPCopyDecBuffer(&output, keep_info); - } - // return decoded samples (don't clear 'output'!) - return WebPIsRGBMode(mode) ? output.u.RGBA.rgba : output.u.YUVA.y; -} - -uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size, - int* width, int* height) { - return Decode(MODE_RGB, data, data_size, width, height, NULL); -} - -uint8_t* WebPDecodeRGBA(const uint8_t* data, size_t data_size, - int* width, int* height) { - return Decode(MODE_RGBA, data, data_size, width, height, NULL); -} - -uint8_t* WebPDecodeARGB(const uint8_t* data, size_t data_size, - int* width, int* height) { - return Decode(MODE_ARGB, data, data_size, width, height, NULL); -} - -uint8_t* WebPDecodeBGR(const uint8_t* data, size_t data_size, - int* width, int* height) { - return Decode(MODE_BGR, data, data_size, width, height, NULL); -} - -uint8_t* WebPDecodeBGRA(const uint8_t* data, size_t data_size, - int* width, int* height) { - return Decode(MODE_BGRA, data, data_size, width, height, NULL); -} - -uint8_t* WebPDecodeYUV(const uint8_t* data, size_t data_size, - int* width, int* height, uint8_t** u, uint8_t** v, - int* stride, int* uv_stride) { - WebPDecBuffer output; // only to preserve the side-infos - uint8_t* const out = Decode(MODE_YUV, data, data_size, - width, height, &output); - - if (out != NULL) { - const WebPYUVABuffer* const buf = &output.u.YUVA; - *u = buf->u; - *v = buf->v; - *stride = buf->y_stride; - *uv_stride = buf->u_stride; - assert(buf->u_stride == buf->v_stride); - } - return out; -} - -static void DefaultFeatures(WebPBitstreamFeatures* const features) { - assert(features != NULL); - memset(features, 0, sizeof(*features)); -} - -static VP8StatusCode GetFeatures(const uint8_t* const data, size_t data_size, - WebPBitstreamFeatures* const features) { - if (features == NULL || data == NULL) { - return VP8_STATUS_INVALID_PARAM; - } - DefaultFeatures(features); - - // Only parse enough of the data to retrieve the features. - return ParseHeadersInternal(data, data_size, - &features->width, &features->height, - &features->has_alpha, &features->has_animation, - &features->format, NULL); -} - -//------------------------------------------------------------------------------ -// WebPGetInfo() - -int WebPGetInfo(const uint8_t* data, size_t data_size, - int* width, int* height) { - WebPBitstreamFeatures features; - - if (GetFeatures(data, data_size, &features) != VP8_STATUS_OK) { - return 0; - } - - if (width != NULL) { - *width = features.width; - } - if (height != NULL) { - *height = features.height; - } - - return 1; -} - -//------------------------------------------------------------------------------ -// Advance decoding API - -int WebPInitDecoderConfigInternal(WebPDecoderConfig* config, - int version) { - if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) { - return 0; // version mismatch - } - if (config == NULL) { - return 0; - } - memset(config, 0, sizeof(*config)); - DefaultFeatures(&config->input); - WebPInitDecBuffer(&config->output); - return 1; -} - -VP8StatusCode WebPGetFeaturesInternal(const uint8_t* data, size_t data_size, - WebPBitstreamFeatures* features, - int version) { - if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) { - return VP8_STATUS_INVALID_PARAM; // version mismatch - } - if (features == NULL) { - return VP8_STATUS_INVALID_PARAM; - } - return GetFeatures(data, data_size, features); -} - -VP8StatusCode WebPDecode(const uint8_t* data, size_t data_size, - WebPDecoderConfig* config) { - WebPDecParams params; - VP8StatusCode status; - - if (config == NULL) { - return VP8_STATUS_INVALID_PARAM; - } - - status = GetFeatures(data, data_size, &config->input); - if (status != VP8_STATUS_OK) { - if (status == VP8_STATUS_NOT_ENOUGH_DATA) { - return VP8_STATUS_BITSTREAM_ERROR; // Not-enough-data treated as error. - } - return status; - } - - WebPResetDecParams(¶ms); - params.options = &config->options; - params.output = &config->output; - if (WebPAvoidSlowMemory(params.output, &config->input)) { - // decoding to slow memory: use a temporary in-mem buffer to decode into. - WebPDecBuffer in_mem_buffer; - WebPInitDecBuffer(&in_mem_buffer); - in_mem_buffer.colorspace = config->output.colorspace; - in_mem_buffer.width = config->input.width; - in_mem_buffer.height = config->input.height; - params.output = &in_mem_buffer; - status = DecodeInto(data, data_size, ¶ms); - if (status == VP8_STATUS_OK) { // do the slow-copy - status = WebPCopyDecBufferPixels(&in_mem_buffer, &config->output); - } - WebPFreeDecBuffer(&in_mem_buffer); - } else { - status = DecodeInto(data, data_size, ¶ms); - } - - return status; -} - -//------------------------------------------------------------------------------ -// Cropping and rescaling. - -int WebPIoInitFromOptions(const WebPDecoderOptions* const options, - VP8Io* const io, WEBP_CSP_MODE src_colorspace) { - const int W = io->width; - const int H = io->height; - int x = 0, y = 0, w = W, h = H; - - // Cropping - io->use_cropping = (options != NULL) && (options->use_cropping > 0); - if (io->use_cropping) { - w = options->crop_width; - h = options->crop_height; - x = options->crop_left; - y = options->crop_top; - if (!WebPIsRGBMode(src_colorspace)) { // only snap for YUV420 - x &= ~1; - y &= ~1; - } - if (x < 0 || y < 0 || w <= 0 || h <= 0 || x + w > W || y + h > H) { - return 0; // out of frame boundary error - } - } - io->crop_left = x; - io->crop_top = y; - io->crop_right = x + w; - io->crop_bottom = y + h; - io->mb_w = w; - io->mb_h = h; - - // Scaling - io->use_scaling = (options != NULL) && (options->use_scaling > 0); - if (io->use_scaling) { - int scaled_width = options->scaled_width; - int scaled_height = options->scaled_height; - if (!WebPRescalerGetScaledDimensions(w, h, &scaled_width, &scaled_height)) { - return 0; - } - io->scaled_width = scaled_width; - io->scaled_height = scaled_height; - } - - // Filter - io->bypass_filtering = (options != NULL) && options->bypass_filtering; - - // Fancy upsampler -#ifdef FANCY_UPSAMPLING - io->fancy_upsampling = (options == NULL) || (!options->no_fancy_upsampling); -#endif - - if (io->use_scaling) { - // disable filter (only for large downscaling ratio). - io->bypass_filtering = (io->scaled_width < W * 3 / 4) && - (io->scaled_height < H * 3 / 4); - io->fancy_upsampling = 0; - } - return 1; -} - -//------------------------------------------------------------------------------ |