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authorwolfbeast <mcwerewolf@gmail.com>2017-07-24 13:19:25 +0200
committerwolfbeast <mcwerewolf@gmail.com>2018-02-03 09:57:42 +0100
commit2c1f833a092ef7af17f072749940bcb47da19aa6 (patch)
treee1904491a9c9a745d77df2225b679d921156affc /media/libwebp/dec/webp_dec.c
parentc0cfd6f89cd6b25cc8aaea1a1eb7bc004c88c206 (diff)
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Add libwebp 0.6.0 to the tree
Diffstat (limited to 'media/libwebp/dec/webp_dec.c')
-rw-r--r--media/libwebp/dec/webp_dec.c843
1 files changed, 843 insertions, 0 deletions
diff --git a/media/libwebp/dec/webp_dec.c b/media/libwebp/dec/webp_dec.c
new file mode 100644
index 000000000..a8e9c2c51
--- /dev/null
+++ b/media/libwebp/dec/webp_dec.c
@@ -0,0 +1,843 @@
+// 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_dec.h"
+#include "./vp8li_dec.h"
+#include "./webpi_dec.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, 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;
+ 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);
+ 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 && 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) {
+ *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(&params);
+ 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, &params) != 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(&params);
+ 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, &params) != 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(&params);
+ 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, &params) != 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(&params);
+ 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, &params);
+ 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, &params);
+ }
+
+ 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;
+}
+
+//------------------------------------------------------------------------------