summaryrefslogtreecommitdiff
path: root/drivers/webp/dec/vp8.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/webp/dec/vp8.c')
-rw-r--r--drivers/webp/dec/vp8.c667
1 files changed, 0 insertions, 667 deletions
diff --git a/drivers/webp/dec/vp8.c b/drivers/webp/dec/vp8.c
deleted file mode 100644
index 336680c38c..0000000000
--- a/drivers/webp/dec/vp8.c
+++ /dev/null
@@ -1,667 +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 entry for the decoder
-//
-// Author: Skal (pascal.massimino@gmail.com)
-
-#include <stdlib.h>
-
-#include "./alphai.h"
-#include "./vp8i.h"
-#include "./vp8li.h"
-#include "./webpi.h"
-#include "../utils/bit_reader_inl.h"
-#include "../utils/utils.h"
-
-//------------------------------------------------------------------------------
-
-int WebPGetDecoderVersion(void) {
- return (DEC_MAJ_VERSION << 16) | (DEC_MIN_VERSION << 8) | DEC_REV_VERSION;
-}
-
-//------------------------------------------------------------------------------
-// VP8Decoder
-
-static void SetOk(VP8Decoder* const dec) {
- dec->status_ = VP8_STATUS_OK;
- dec->error_msg_ = "OK";
-}
-
-int VP8InitIoInternal(VP8Io* const io, int version) {
- if (WEBP_ABI_IS_INCOMPATIBLE(version, WEBP_DECODER_ABI_VERSION)) {
- return 0; // mismatch error
- }
- if (io != NULL) {
- memset(io, 0, sizeof(*io));
- }
- return 1;
-}
-
-VP8Decoder* VP8New(void) {
- VP8Decoder* const dec = (VP8Decoder*)WebPSafeCalloc(1ULL, sizeof(*dec));
- if (dec != NULL) {
- SetOk(dec);
- WebPGetWorkerInterface()->Init(&dec->worker_);
- dec->ready_ = 0;
- dec->num_parts_minus_one_ = 0;
- }
- return dec;
-}
-
-VP8StatusCode VP8Status(VP8Decoder* const dec) {
- if (!dec) return VP8_STATUS_INVALID_PARAM;
- return dec->status_;
-}
-
-const char* VP8StatusMessage(VP8Decoder* const dec) {
- if (dec == NULL) return "no object";
- if (!dec->error_msg_) return "OK";
- return dec->error_msg_;
-}
-
-void VP8Delete(VP8Decoder* const dec) {
- if (dec != NULL) {
- VP8Clear(dec);
- WebPSafeFree(dec);
- }
-}
-
-int VP8SetError(VP8Decoder* const dec,
- VP8StatusCode error, const char* const msg) {
- // The oldest error reported takes precedence over the new one.
- if (dec->status_ == VP8_STATUS_OK) {
- dec->status_ = error;
- dec->error_msg_ = msg;
- dec->ready_ = 0;
- }
- return 0;
-}
-
-//------------------------------------------------------------------------------
-
-int VP8CheckSignature(const uint8_t* const data, size_t data_size) {
- return (data_size >= 3 &&
- data[0] == 0x9d && data[1] == 0x01 && data[2] == 0x2a);
-}
-
-int VP8GetInfo(const uint8_t* data, size_t data_size, size_t chunk_size,
- int* const width, int* const height) {
- if (data == NULL || data_size < VP8_FRAME_HEADER_SIZE) {
- return 0; // not enough data
- }
- // check signature
- if (!VP8CheckSignature(data + 3, data_size - 3)) {
- return 0; // Wrong signature.
- } else {
- const uint32_t bits = data[0] | (data[1] << 8) | (data[2] << 16);
- const int key_frame = !(bits & 1);
- const int w = ((data[7] << 8) | data[6]) & 0x3fff;
- const int h = ((data[9] << 8) | data[8]) & 0x3fff;
-
- if (!key_frame) { // Not a keyframe.
- return 0;
- }
-
- if (((bits >> 1) & 7) > 3) {
- return 0; // unknown profile
- }
- if (!((bits >> 4) & 1)) {
- return 0; // first frame is invisible!
- }
- if (((bits >> 5)) >= chunk_size) { // partition_length
- return 0; // inconsistent size information.
- }
- if (w == 0 || h == 0) {
- return 0; // We don't support both width and height to be zero.
- }
-
- if (width) {
- *width = w;
- }
- if (height) {
- *height = h;
- }
-
- return 1;
- }
-}
-
-//------------------------------------------------------------------------------
-// Header parsing
-
-static void ResetSegmentHeader(VP8SegmentHeader* const hdr) {
- assert(hdr != NULL);
- hdr->use_segment_ = 0;
- hdr->update_map_ = 0;
- hdr->absolute_delta_ = 1;
- memset(hdr->quantizer_, 0, sizeof(hdr->quantizer_));
- memset(hdr->filter_strength_, 0, sizeof(hdr->filter_strength_));
-}
-
-// Paragraph 9.3
-static int ParseSegmentHeader(VP8BitReader* br,
- VP8SegmentHeader* hdr, VP8Proba* proba) {
- assert(br != NULL);
- assert(hdr != NULL);
- hdr->use_segment_ = VP8Get(br);
- if (hdr->use_segment_) {
- hdr->update_map_ = VP8Get(br);
- if (VP8Get(br)) { // update data
- int s;
- hdr->absolute_delta_ = VP8Get(br);
- for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
- hdr->quantizer_[s] = VP8Get(br) ? VP8GetSignedValue(br, 7) : 0;
- }
- for (s = 0; s < NUM_MB_SEGMENTS; ++s) {
- hdr->filter_strength_[s] = VP8Get(br) ? VP8GetSignedValue(br, 6) : 0;
- }
- }
- if (hdr->update_map_) {
- int s;
- for (s = 0; s < MB_FEATURE_TREE_PROBS; ++s) {
- proba->segments_[s] = VP8Get(br) ? VP8GetValue(br, 8) : 255u;
- }
- }
- } else {
- hdr->update_map_ = 0;
- }
- return !br->eof_;
-}
-
-// Paragraph 9.5
-// This function returns VP8_STATUS_SUSPENDED if we don't have all the
-// necessary data in 'buf'.
-// This case is not necessarily an error (for incremental decoding).
-// Still, no bitreader is ever initialized to make it possible to read
-// unavailable memory.
-// If we don't even have the partitions' sizes, than VP8_STATUS_NOT_ENOUGH_DATA
-// is returned, and this is an unrecoverable error.
-// If the partitions were positioned ok, VP8_STATUS_OK is returned.
-static VP8StatusCode ParsePartitions(VP8Decoder* const dec,
- const uint8_t* buf, size_t size) {
- VP8BitReader* const br = &dec->br_;
- const uint8_t* sz = buf;
- const uint8_t* buf_end = buf + size;
- const uint8_t* part_start;
- size_t size_left = size;
- size_t last_part;
- size_t p;
-
- dec->num_parts_minus_one_ = (1 << VP8GetValue(br, 2)) - 1;
- last_part = dec->num_parts_minus_one_;
- if (size < 3 * last_part) {
- // we can't even read the sizes with sz[]! That's a failure.
- return VP8_STATUS_NOT_ENOUGH_DATA;
- }
- part_start = buf + last_part * 3;
- size_left -= last_part * 3;
- for (p = 0; p < last_part; ++p) {
- size_t psize = sz[0] | (sz[1] << 8) | (sz[2] << 16);
- if (psize > size_left) psize = size_left;
- VP8InitBitReader(dec->parts_ + p, part_start, psize);
- part_start += psize;
- size_left -= psize;
- sz += 3;
- }
- VP8InitBitReader(dec->parts_ + last_part, part_start, size_left);
- return (part_start < buf_end) ? VP8_STATUS_OK :
- VP8_STATUS_SUSPENDED; // Init is ok, but there's not enough data
-}
-
-// Paragraph 9.4
-static int ParseFilterHeader(VP8BitReader* br, VP8Decoder* const dec) {
- VP8FilterHeader* const hdr = &dec->filter_hdr_;
- hdr->simple_ = VP8Get(br);
- hdr->level_ = VP8GetValue(br, 6);
- hdr->sharpness_ = VP8GetValue(br, 3);
- hdr->use_lf_delta_ = VP8Get(br);
- if (hdr->use_lf_delta_) {
- if (VP8Get(br)) { // update lf-delta?
- int i;
- for (i = 0; i < NUM_REF_LF_DELTAS; ++i) {
- if (VP8Get(br)) {
- hdr->ref_lf_delta_[i] = VP8GetSignedValue(br, 6);
- }
- }
- for (i = 0; i < NUM_MODE_LF_DELTAS; ++i) {
- if (VP8Get(br)) {
- hdr->mode_lf_delta_[i] = VP8GetSignedValue(br, 6);
- }
- }
- }
- }
- dec->filter_type_ = (hdr->level_ == 0) ? 0 : hdr->simple_ ? 1 : 2;
- return !br->eof_;
-}
-
-// Topmost call
-int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
- const uint8_t* buf;
- size_t buf_size;
- VP8FrameHeader* frm_hdr;
- VP8PictureHeader* pic_hdr;
- VP8BitReader* br;
- VP8StatusCode status;
-
- if (dec == NULL) {
- return 0;
- }
- SetOk(dec);
- if (io == NULL) {
- return VP8SetError(dec, VP8_STATUS_INVALID_PARAM,
- "null VP8Io passed to VP8GetHeaders()");
- }
- buf = io->data;
- buf_size = io->data_size;
- if (buf_size < 4) {
- return VP8SetError(dec, VP8_STATUS_NOT_ENOUGH_DATA,
- "Truncated header.");
- }
-
- // Paragraph 9.1
- {
- const uint32_t bits = buf[0] | (buf[1] << 8) | (buf[2] << 16);
- frm_hdr = &dec->frm_hdr_;
- frm_hdr->key_frame_ = !(bits & 1);
- frm_hdr->profile_ = (bits >> 1) & 7;
- frm_hdr->show_ = (bits >> 4) & 1;
- frm_hdr->partition_length_ = (bits >> 5);
- if (frm_hdr->profile_ > 3)
- return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR,
- "Incorrect keyframe parameters.");
- if (!frm_hdr->show_)
- return VP8SetError(dec, VP8_STATUS_UNSUPPORTED_FEATURE,
- "Frame not displayable.");
- buf += 3;
- buf_size -= 3;
- }
-
- pic_hdr = &dec->pic_hdr_;
- if (frm_hdr->key_frame_) {
- // Paragraph 9.2
- if (buf_size < 7) {
- return VP8SetError(dec, VP8_STATUS_NOT_ENOUGH_DATA,
- "cannot parse picture header");
- }
- if (!VP8CheckSignature(buf, buf_size)) {
- return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR,
- "Bad code word");
- }
- pic_hdr->width_ = ((buf[4] << 8) | buf[3]) & 0x3fff;
- pic_hdr->xscale_ = buf[4] >> 6; // ratio: 1, 5/4 5/3 or 2
- pic_hdr->height_ = ((buf[6] << 8) | buf[5]) & 0x3fff;
- pic_hdr->yscale_ = buf[6] >> 6;
- buf += 7;
- buf_size -= 7;
-
- dec->mb_w_ = (pic_hdr->width_ + 15) >> 4;
- dec->mb_h_ = (pic_hdr->height_ + 15) >> 4;
-
- // Setup default output area (can be later modified during io->setup())
- io->width = pic_hdr->width_;
- io->height = pic_hdr->height_;
- // IMPORTANT! use some sane dimensions in crop_* and scaled_* fields.
- // So they can be used interchangeably without always testing for
- // 'use_cropping'.
- io->use_cropping = 0;
- io->crop_top = 0;
- io->crop_left = 0;
- io->crop_right = io->width;
- io->crop_bottom = io->height;
- io->use_scaling = 0;
- io->scaled_width = io->width;
- io->scaled_height = io->height;
-
- io->mb_w = io->width; // sanity check
- io->mb_h = io->height; // ditto
-
- VP8ResetProba(&dec->proba_);
- ResetSegmentHeader(&dec->segment_hdr_);
- }
-
- // Check if we have all the partition #0 available, and initialize dec->br_
- // to read this partition (and this partition only).
- if (frm_hdr->partition_length_ > buf_size) {
- return VP8SetError(dec, VP8_STATUS_NOT_ENOUGH_DATA,
- "bad partition length");
- }
-
- br = &dec->br_;
- VP8InitBitReader(br, buf, frm_hdr->partition_length_);
- buf += frm_hdr->partition_length_;
- buf_size -= frm_hdr->partition_length_;
-
- if (frm_hdr->key_frame_) {
- pic_hdr->colorspace_ = VP8Get(br);
- pic_hdr->clamp_type_ = VP8Get(br);
- }
- if (!ParseSegmentHeader(br, &dec->segment_hdr_, &dec->proba_)) {
- return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR,
- "cannot parse segment header");
- }
- // Filter specs
- if (!ParseFilterHeader(br, dec)) {
- return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR,
- "cannot parse filter header");
- }
- status = ParsePartitions(dec, buf, buf_size);
- if (status != VP8_STATUS_OK) {
- return VP8SetError(dec, status, "cannot parse partitions");
- }
-
- // quantizer change
- VP8ParseQuant(dec);
-
- // Frame buffer marking
- if (!frm_hdr->key_frame_) {
- return VP8SetError(dec, VP8_STATUS_UNSUPPORTED_FEATURE,
- "Not a key frame.");
- }
-
- VP8Get(br); // ignore the value of update_proba_
-
- VP8ParseProba(br, dec);
-
- // sanitized state
- dec->ready_ = 1;
- return 1;
-}
-
-//------------------------------------------------------------------------------
-// Residual decoding (Paragraph 13.2 / 13.3)
-
-static const uint8_t kCat3[] = { 173, 148, 140, 0 };
-static const uint8_t kCat4[] = { 176, 155, 140, 135, 0 };
-static const uint8_t kCat5[] = { 180, 157, 141, 134, 130, 0 };
-static const uint8_t kCat6[] =
- { 254, 254, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0 };
-static const uint8_t* const kCat3456[] = { kCat3, kCat4, kCat5, kCat6 };
-static const uint8_t kZigzag[16] = {
- 0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15
-};
-
-// See section 13-2: http://tools.ietf.org/html/rfc6386#section-13.2
-static int GetLargeValue(VP8BitReader* const br, const uint8_t* const p) {
- int v;
- if (!VP8GetBit(br, p[3])) {
- if (!VP8GetBit(br, p[4])) {
- v = 2;
- } else {
- v = 3 + VP8GetBit(br, p[5]);
- }
- } else {
- if (!VP8GetBit(br, p[6])) {
- if (!VP8GetBit(br, p[7])) {
- v = 5 + VP8GetBit(br, 159);
- } else {
- v = 7 + 2 * VP8GetBit(br, 165);
- v += VP8GetBit(br, 145);
- }
- } else {
- const uint8_t* tab;
- const int bit1 = VP8GetBit(br, p[8]);
- const int bit0 = VP8GetBit(br, p[9 + bit1]);
- const int cat = 2 * bit1 + bit0;
- v = 0;
- for (tab = kCat3456[cat]; *tab; ++tab) {
- v += v + VP8GetBit(br, *tab);
- }
- v += 3 + (8 << cat);
- }
- }
- return v;
-}
-
-// Returns the position of the last non-zero coeff plus one
-static int GetCoeffs(VP8BitReader* const br, const VP8BandProbas* const prob[],
- int ctx, const quant_t dq, int n, int16_t* out) {
- const uint8_t* p = prob[n]->probas_[ctx];
- for (; n < 16; ++n) {
- if (!VP8GetBit(br, p[0])) {
- return n; // previous coeff was last non-zero coeff
- }
- while (!VP8GetBit(br, p[1])) { // sequence of zero coeffs
- p = prob[++n]->probas_[0];
- if (n == 16) return 16;
- }
- { // non zero coeff
- const VP8ProbaArray* const p_ctx = &prob[n + 1]->probas_[0];
- int v;
- if (!VP8GetBit(br, p[2])) {
- v = 1;
- p = p_ctx[1];
- } else {
- v = GetLargeValue(br, p);
- p = p_ctx[2];
- }
- out[kZigzag[n]] = VP8GetSigned(br, v) * dq[n > 0];
- }
- }
- return 16;
-}
-
-static WEBP_INLINE uint32_t NzCodeBits(uint32_t nz_coeffs, int nz, int dc_nz) {
- nz_coeffs <<= 2;
- nz_coeffs |= (nz > 3) ? 3 : (nz > 1) ? 2 : dc_nz;
- return nz_coeffs;
-}
-
-static int ParseResiduals(VP8Decoder* const dec,
- VP8MB* const mb, VP8BitReader* const token_br) {
- const VP8BandProbas* (* const bands)[16 + 1] = dec->proba_.bands_ptr_;
- const VP8BandProbas* const * ac_proba;
- VP8MBData* const block = dec->mb_data_ + dec->mb_x_;
- const VP8QuantMatrix* const q = &dec->dqm_[block->segment_];
- int16_t* dst = block->coeffs_;
- VP8MB* const left_mb = dec->mb_info_ - 1;
- uint8_t tnz, lnz;
- uint32_t non_zero_y = 0;
- uint32_t non_zero_uv = 0;
- int x, y, ch;
- uint32_t out_t_nz, out_l_nz;
- int first;
-
- memset(dst, 0, 384 * sizeof(*dst));
- if (!block->is_i4x4_) { // parse DC
- int16_t dc[16] = { 0 };
- const int ctx = mb->nz_dc_ + left_mb->nz_dc_;
- const int nz = GetCoeffs(token_br, bands[1], ctx, q->y2_mat_, 0, dc);
- mb->nz_dc_ = left_mb->nz_dc_ = (nz > 0);
- if (nz > 1) { // more than just the DC -> perform the full transform
- VP8TransformWHT(dc, dst);
- } else { // only DC is non-zero -> inlined simplified transform
- int i;
- const int dc0 = (dc[0] + 3) >> 3;
- for (i = 0; i < 16 * 16; i += 16) dst[i] = dc0;
- }
- first = 1;
- ac_proba = bands[0];
- } else {
- first = 0;
- ac_proba = bands[3];
- }
-
- tnz = mb->nz_ & 0x0f;
- lnz = left_mb->nz_ & 0x0f;
- for (y = 0; y < 4; ++y) {
- int l = lnz & 1;
- uint32_t nz_coeffs = 0;
- for (x = 0; x < 4; ++x) {
- const int ctx = l + (tnz & 1);
- const int nz = GetCoeffs(token_br, ac_proba, ctx, q->y1_mat_, first, dst);
- l = (nz > first);
- tnz = (tnz >> 1) | (l << 7);
- nz_coeffs = NzCodeBits(nz_coeffs, nz, dst[0] != 0);
- dst += 16;
- }
- tnz >>= 4;
- lnz = (lnz >> 1) | (l << 7);
- non_zero_y = (non_zero_y << 8) | nz_coeffs;
- }
- out_t_nz = tnz;
- out_l_nz = lnz >> 4;
-
- for (ch = 0; ch < 4; ch += 2) {
- uint32_t nz_coeffs = 0;
- tnz = mb->nz_ >> (4 + ch);
- lnz = left_mb->nz_ >> (4 + ch);
- for (y = 0; y < 2; ++y) {
- int l = lnz & 1;
- for (x = 0; x < 2; ++x) {
- const int ctx = l + (tnz & 1);
- const int nz = GetCoeffs(token_br, bands[2], ctx, q->uv_mat_, 0, dst);
- l = (nz > 0);
- tnz = (tnz >> 1) | (l << 3);
- nz_coeffs = NzCodeBits(nz_coeffs, nz, dst[0] != 0);
- dst += 16;
- }
- tnz >>= 2;
- lnz = (lnz >> 1) | (l << 5);
- }
- // Note: we don't really need the per-4x4 details for U/V blocks.
- non_zero_uv |= nz_coeffs << (4 * ch);
- out_t_nz |= (tnz << 4) << ch;
- out_l_nz |= (lnz & 0xf0) << ch;
- }
- mb->nz_ = out_t_nz;
- left_mb->nz_ = out_l_nz;
-
- block->non_zero_y_ = non_zero_y;
- block->non_zero_uv_ = non_zero_uv;
-
- // We look at the mode-code of each block and check if some blocks have less
- // than three non-zero coeffs (code < 2). This is to avoid dithering flat and
- // empty blocks.
- block->dither_ = (non_zero_uv & 0xaaaa) ? 0 : q->dither_;
-
- return !(non_zero_y | non_zero_uv); // will be used for further optimization
-}
-
-//------------------------------------------------------------------------------
-// Main loop
-
-int VP8DecodeMB(VP8Decoder* const dec, VP8BitReader* const token_br) {
- VP8MB* const left = dec->mb_info_ - 1;
- VP8MB* const mb = dec->mb_info_ + dec->mb_x_;
- VP8MBData* const block = dec->mb_data_ + dec->mb_x_;
- int skip = dec->use_skip_proba_ ? block->skip_ : 0;
-
- if (!skip) {
- skip = ParseResiduals(dec, mb, token_br);
- } else {
- left->nz_ = mb->nz_ = 0;
- if (!block->is_i4x4_) {
- left->nz_dc_ = mb->nz_dc_ = 0;
- }
- block->non_zero_y_ = 0;
- block->non_zero_uv_ = 0;
- block->dither_ = 0;
- }
-
- if (dec->filter_type_ > 0) { // store filter info
- VP8FInfo* const finfo = dec->f_info_ + dec->mb_x_;
- *finfo = dec->fstrengths_[block->segment_][block->is_i4x4_];
- finfo->f_inner_ |= !skip;
- }
-
- return !token_br->eof_;
-}
-
-void VP8InitScanline(VP8Decoder* const dec) {
- VP8MB* const left = dec->mb_info_ - 1;
- left->nz_ = 0;
- left->nz_dc_ = 0;
- memset(dec->intra_l_, B_DC_PRED, sizeof(dec->intra_l_));
- dec->mb_x_ = 0;
-}
-
-static int ParseFrame(VP8Decoder* const dec, VP8Io* io) {
- for (dec->mb_y_ = 0; dec->mb_y_ < dec->br_mb_y_; ++dec->mb_y_) {
- // Parse bitstream for this row.
- VP8BitReader* const token_br =
- &dec->parts_[dec->mb_y_ & dec->num_parts_minus_one_];
- if (!VP8ParseIntraModeRow(&dec->br_, dec)) {
- return VP8SetError(dec, VP8_STATUS_NOT_ENOUGH_DATA,
- "Premature end-of-partition0 encountered.");
- }
- for (; dec->mb_x_ < dec->mb_w_; ++dec->mb_x_) {
- if (!VP8DecodeMB(dec, token_br)) {
- return VP8SetError(dec, VP8_STATUS_NOT_ENOUGH_DATA,
- "Premature end-of-file encountered.");
- }
- }
- VP8InitScanline(dec); // Prepare for next scanline
-
- // Reconstruct, filter and emit the row.
- if (!VP8ProcessRow(dec, io)) {
- return VP8SetError(dec, VP8_STATUS_USER_ABORT, "Output aborted.");
- }
- }
- if (dec->mt_method_ > 0) {
- if (!WebPGetWorkerInterface()->Sync(&dec->worker_)) return 0;
- }
-
- return 1;
-}
-
-// Main entry point
-int VP8Decode(VP8Decoder* const dec, VP8Io* const io) {
- int ok = 0;
- if (dec == NULL) {
- return 0;
- }
- if (io == NULL) {
- return VP8SetError(dec, VP8_STATUS_INVALID_PARAM,
- "NULL VP8Io parameter in VP8Decode().");
- }
-
- if (!dec->ready_) {
- if (!VP8GetHeaders(dec, io)) {
- return 0;
- }
- }
- assert(dec->ready_);
-
- // Finish setting up the decoding parameter. Will call io->setup().
- ok = (VP8EnterCritical(dec, io) == VP8_STATUS_OK);
- if (ok) { // good to go.
- // Will allocate memory and prepare everything.
- if (ok) ok = VP8InitFrame(dec, io);
-
- // Main decoding loop
- if (ok) ok = ParseFrame(dec, io);
-
- // Exit.
- ok &= VP8ExitCritical(dec, io);
- }
-
- if (!ok) {
- VP8Clear(dec);
- return 0;
- }
-
- dec->ready_ = 0;
- return ok;
-}
-
-void VP8Clear(VP8Decoder* const dec) {
- if (dec == NULL) {
- return;
- }
- WebPGetWorkerInterface()->End(&dec->worker_);
- WebPDeallocateAlphaMemory(dec);
- WebPSafeFree(dec->mem_);
- dec->mem_ = NULL;
- dec->mem_size_ = 0;
- memset(&dec->br_, 0, sizeof(dec->br_));
- dec->ready_ = 0;
-}
-
-//------------------------------------------------------------------------------