diff options
Diffstat (limited to 'drivers/webpold/dec/vp8.c')
| -rw-r--r-- | drivers/webpold/dec/vp8.c | 787 |
1 files changed, 0 insertions, 787 deletions
diff --git a/drivers/webpold/dec/vp8.c b/drivers/webpold/dec/vp8.c deleted file mode 100644 index b0ccfa2a06..0000000000 --- a/drivers/webpold/dec/vp8.c +++ /dev/null @@ -1,787 +0,0 @@ -// Copyright 2010 Google Inc. All Rights Reserved. -// -// This code is licensed under the same terms as WebM: -// Software License Agreement: http://www.webmproject.org/license/software/ -// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ -// ----------------------------------------------------------------------------- -// -// main entry for the decoder -// -// Author: Skal (pascal.massimino@gmail.com) - -#include <stdlib.h> - -#include "./vp8i.h" -#include "./vp8li.h" -#include "./webpi.h" -#include "../utils/bit_reader.h" - -#if defined(__cplusplus) || defined(c_plusplus) -extern "C" { -#endif - -//------------------------------------------------------------------------------ - -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*)calloc(1, sizeof(*dec)); - if (dec != NULL) { - SetOk(dec); - WebPWorkerInit(&dec->worker_); - dec->ready_ = 0; - dec->num_parts_ = 1; - } - 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); - free(dec); - } -} - -int VP8SetError(VP8Decoder* const dec, - VP8StatusCode error, const char* const msg) { - // TODO This check would be unnecessary if alpha decompression was separated - // from VP8ProcessRow/FinishRow. This avoids setting 'dec->status_' to - // something other than VP8_STATUS_BITSTREAM_ERROR on alpha decompression - // failure. - 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 (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; - int last_part; - int p; - - dec->num_parts_ = 1 << VP8GetValue(br, 2); - last_part = dec->num_parts_ - 1; - part_start = buf + last_part * 3; - if (buf_end < part_start) { - // we can't even read the sizes with sz[]! That's a failure. - return VP8_STATUS_NOT_ENOUGH_DATA; - } - for (p = 0; p < last_part; ++p) { - const uint32_t psize = sz[0] | (sz[1] << 8) | (sz[2] << 16); - const uint8_t* part_end = part_start + psize; - if (part_end > buf_end) part_end = buf_end; - VP8InitBitReader(dec->parts_ + p, part_start, part_end); - part_start = part_end; - sz += 3; - } - VP8InitBitReader(dec->parts_ + last_part, part_start, buf_end); - 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; - if (dec->filter_type_ > 0) { // precompute filter levels per segment - if (dec->segment_hdr_.use_segment_) { - int s; - for (s = 0; s < NUM_MB_SEGMENTS; ++s) { - int strength = dec->segment_hdr_.filter_strength_[s]; - if (!dec->segment_hdr_.absolute_delta_) { - strength += hdr->level_; - } - dec->filter_levels_[s] = strength; - } - } else { - dec->filter_levels_[0] = hdr->level_; - } - } - 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; - WebPHeaderStructure headers; - - if (dec == NULL) { - return 0; - } - SetOk(dec); - if (io == NULL) { - return VP8SetError(dec, VP8_STATUS_INVALID_PARAM, - "null VP8Io passed to VP8GetHeaders()"); - } - - // Process Pre-VP8 chunks. - headers.data = io->data; - headers.data_size = io->data_size; - status = WebPParseHeaders(&headers); - if (status != VP8_STATUS_OK) { - return VP8SetError(dec, status, "Incorrect/incomplete header."); - } - if (headers.is_lossless) { - return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR, - "Unexpected lossless format encountered."); - } - - if (dec->alpha_data_ == NULL) { - assert(dec->alpha_data_size_ == 0); - // We have NOT set alpha data yet. Set it now. - // (This is to ensure that dec->alpha_data_ is NOT reset to NULL if - // WebPParseHeaders() is called more than once, as in incremental decoding - // case.) - dec->alpha_data_ = headers.alpha_data; - dec->alpha_data_size_ = headers.alpha_data_size; - } - - // Process the VP8 frame header. - buf = headers.data + headers.offset; - buf_size = headers.data_size - headers.offset; - assert(headers.data_size >= headers.offset); // WebPParseHeaders' guarantee - 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_; - io->use_scaling = 0; - io->use_cropping = 0; - io->crop_top = 0; - io->crop_left = 0; - io->crop_right = io->width; - io->crop_bottom = io->height; - io->mb_w = io->width; // sanity check - io->mb_h = io->height; // ditto - - VP8ResetProba(&dec->proba_); - ResetSegmentHeader(&dec->segment_hdr_); - dec->segment_ = 0; // default for intra - } - - // 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, 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_) { - // Paragraph 9.7 -#ifndef ONLY_KEYFRAME_CODE - dec->buffer_flags_ = VP8Get(br) << 0; // update golden - dec->buffer_flags_ |= VP8Get(br) << 1; // update alt ref - if (!(dec->buffer_flags_ & 1)) { - dec->buffer_flags_ |= VP8GetValue(br, 2) << 2; - } - if (!(dec->buffer_flags_ & 2)) { - dec->buffer_flags_ |= VP8GetValue(br, 2) << 4; - } - dec->buffer_flags_ |= VP8Get(br) << 6; // sign bias golden - dec->buffer_flags_ |= VP8Get(br) << 7; // sign bias alt ref -#else - return VP8SetError(dec, VP8_STATUS_UNSUPPORTED_FEATURE, - "Not a key frame."); -#endif - } else { - dec->buffer_flags_ = 0x003 | 0x100; - } - - // Paragraph 9.8 -#ifndef ONLY_KEYFRAME_CODE - dec->update_proba_ = VP8Get(br); - if (!dec->update_proba_) { // save for later restore - dec->proba_saved_ = dec->proba_; - } - dec->buffer_flags_ &= 1 << 8; - dec->buffer_flags_ |= - (frm_hdr->key_frame_ || VP8Get(br)) << 8; // refresh last frame -#else - VP8Get(br); // just ignore the value of update_proba_ -#endif - - VP8ParseProba(br, dec); - -#ifdef WEBP_EXPERIMENTAL_FEATURES - // Extensions - if (dec->pic_hdr_.colorspace_) { - const size_t kTrailerSize = 8; - const uint8_t kTrailerMarker = 0x01; - const uint8_t* ext_buf = buf - kTrailerSize; - size_t size; - - if (frm_hdr->partition_length_ < kTrailerSize || - ext_buf[kTrailerSize - 1] != kTrailerMarker) { - return VP8SetError(dec, VP8_STATUS_BITSTREAM_ERROR, - "RIFF: Inconsistent extra information."); - } - - // Layer - size = (ext_buf[0] << 0) | (ext_buf[1] << 8) | (ext_buf[2] << 16); - dec->layer_data_size_ = size; - dec->layer_data_ = NULL; // will be set later - dec->layer_colorspace_ = ext_buf[3]; - } -#endif - - // sanitized state - dec->ready_ = 1; - return 1; -} - -//------------------------------------------------------------------------------ -// Residual decoding (Paragraph 13.2 / 13.3) - -static const uint8_t kBands[16 + 1] = { - 0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7, - 0 // extra entry as sentinel -}; - -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 -}; - -typedef const uint8_t (*ProbaArray)[NUM_CTX][NUM_PROBAS]; // for const-casting - -// Returns the position of the last non-zero coeff plus one -// (and 0 if there's no coeff at all) -static int GetCoeffs(VP8BitReader* const br, ProbaArray prob, - int ctx, const quant_t dq, int n, int16_t* out) { - // n is either 0 or 1 here. kBands[n] is not necessary for extracting '*p'. - const uint8_t* p = prob[n][ctx]; - if (!VP8GetBit(br, p[0])) { // first EOB is more a 'CBP' bit. - return 0; - } - while (1) { - ++n; - if (!VP8GetBit(br, p[1])) { - p = prob[kBands[n]][0]; - } else { // non zero coeff - int v, j; - if (!VP8GetBit(br, p[2])) { - p = prob[kBands[n]][1]; - v = 1; - } else { - 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); - } - } - p = prob[kBands[n]][2]; - } - j = kZigzag[n - 1]; - out[j] = VP8GetSigned(br, v) * dq[j > 0]; - if (n == 16 || !VP8GetBit(br, p[0])) { // EOB - return n; - } - } - if (n == 16) { - return 16; - } - } -} - -// Alias-safe way of converting 4bytes to 32bits. -typedef union { - uint8_t i8[4]; - uint32_t i32; -} PackedNz; - -// Table to unpack four bits into four bytes -static const PackedNz kUnpackTab[16] = { - {{0, 0, 0, 0}}, {{1, 0, 0, 0}}, {{0, 1, 0, 0}}, {{1, 1, 0, 0}}, - {{0, 0, 1, 0}}, {{1, 0, 1, 0}}, {{0, 1, 1, 0}}, {{1, 1, 1, 0}}, - {{0, 0, 0, 1}}, {{1, 0, 0, 1}}, {{0, 1, 0, 1}}, {{1, 1, 0, 1}}, - {{0, 0, 1, 1}}, {{1, 0, 1, 1}}, {{0, 1, 1, 1}}, {{1, 1, 1, 1}} }; - -// Macro to pack four LSB of four bytes into four bits. -#if defined(__PPC__) || defined(_M_PPC) || defined(_ARCH_PPC) || \ - defined(__BIG_ENDIAN__) -#define PACK_CST 0x08040201U -#else -#define PACK_CST 0x01020408U -#endif -#define PACK(X, S) ((((X).i32 * PACK_CST) & 0xff000000) >> (S)) - -static void ParseResiduals(VP8Decoder* const dec, - VP8MB* const mb, VP8BitReader* const token_br) { - int out_t_nz, out_l_nz, first; - ProbaArray ac_prob; - const VP8QuantMatrix* q = &dec->dqm_[dec->segment_]; - int16_t* dst = dec->coeffs_; - VP8MB* const left_mb = dec->mb_info_ - 1; - PackedNz nz_ac, nz_dc; - PackedNz tnz, lnz; - uint32_t non_zero_ac = 0; - uint32_t non_zero_dc = 0; - int x, y, ch; - - nz_dc.i32 = nz_ac.i32 = 0; - memset(dst, 0, 384 * sizeof(*dst)); - if (!dec->is_i4x4_) { // parse DC - int16_t dc[16] = { 0 }; - const int ctx = mb->dc_nz_ + left_mb->dc_nz_; - mb->dc_nz_ = left_mb->dc_nz_ = - (GetCoeffs(token_br, (ProbaArray)dec->proba_.coeffs_[1], - ctx, q->y2_mat_, 0, dc) > 0); - first = 1; - ac_prob = (ProbaArray)dec->proba_.coeffs_[0]; - VP8TransformWHT(dc, dst); - } else { - first = 0; - ac_prob = (ProbaArray)dec->proba_.coeffs_[3]; - } - - tnz = kUnpackTab[mb->nz_ & 0xf]; - lnz = kUnpackTab[left_mb->nz_ & 0xf]; - for (y = 0; y < 4; ++y) { - int l = lnz.i8[y]; - for (x = 0; x < 4; ++x) { - const int ctx = l + tnz.i8[x]; - const int nz = GetCoeffs(token_br, ac_prob, ctx, - q->y1_mat_, first, dst); - tnz.i8[x] = l = (nz > 0); - nz_dc.i8[x] = (dst[0] != 0); - nz_ac.i8[x] = (nz > 1); - dst += 16; - } - lnz.i8[y] = l; - non_zero_dc |= PACK(nz_dc, 24 - y * 4); - non_zero_ac |= PACK(nz_ac, 24 - y * 4); - } - out_t_nz = PACK(tnz, 24); - out_l_nz = PACK(lnz, 24); - - tnz = kUnpackTab[mb->nz_ >> 4]; - lnz = kUnpackTab[left_mb->nz_ >> 4]; - for (ch = 0; ch < 4; ch += 2) { - for (y = 0; y < 2; ++y) { - int l = lnz.i8[ch + y]; - for (x = 0; x < 2; ++x) { - const int ctx = l + tnz.i8[ch + x]; - const int nz = - GetCoeffs(token_br, (ProbaArray)dec->proba_.coeffs_[2], - ctx, q->uv_mat_, 0, dst); - tnz.i8[ch + x] = l = (nz > 0); - nz_dc.i8[y * 2 + x] = (dst[0] != 0); - nz_ac.i8[y * 2 + x] = (nz > 1); - dst += 16; - } - lnz.i8[ch + y] = l; - } - non_zero_dc |= PACK(nz_dc, 8 - ch * 2); - non_zero_ac |= PACK(nz_ac, 8 - ch * 2); - } - out_t_nz |= PACK(tnz, 20); - out_l_nz |= PACK(lnz, 20); - mb->nz_ = out_t_nz; - left_mb->nz_ = out_l_nz; - - dec->non_zero_ac_ = non_zero_ac; - dec->non_zero_ = non_zero_ac | non_zero_dc; - mb->skip_ = !dec->non_zero_; -} -#undef PACK - -//------------------------------------------------------------------------------ -// Main loop - -int VP8DecodeMB(VP8Decoder* const dec, VP8BitReader* const token_br) { - VP8BitReader* const br = &dec->br_; - VP8MB* const left = dec->mb_info_ - 1; - VP8MB* const info = dec->mb_info_ + dec->mb_x_; - - // Note: we don't save segment map (yet), as we don't expect - // to decode more than 1 keyframe. - if (dec->segment_hdr_.update_map_) { - // Hardcoded tree parsing - dec->segment_ = !VP8GetBit(br, dec->proba_.segments_[0]) ? - VP8GetBit(br, dec->proba_.segments_[1]) : - 2 + VP8GetBit(br, dec->proba_.segments_[2]); - } - info->skip_ = dec->use_skip_proba_ ? VP8GetBit(br, dec->skip_p_) : 0; - - VP8ParseIntraMode(br, dec); - if (br->eof_) { - return 0; - } - - if (!info->skip_) { - ParseResiduals(dec, info, token_br); - } else { - left->nz_ = info->nz_ = 0; - if (!dec->is_i4x4_) { - left->dc_nz_ = info->dc_nz_ = 0; - } - dec->non_zero_ = 0; - dec->non_zero_ac_ = 0; - } - - return (!token_br->eof_); -} - -void VP8InitScanline(VP8Decoder* const dec) { - VP8MB* const left = dec->mb_info_ - 1; - left->nz_ = 0; - left->dc_nz_ = 0; - memset(dec->intra_l_, B_DC_PRED, sizeof(dec->intra_l_)); - dec->filter_row_ = - (dec->filter_type_ > 0) && - (dec->mb_y_ >= dec->tl_mb_y_) && (dec->mb_y_ <= dec->br_mb_y_); -} - -static int ParseFrame(VP8Decoder* const dec, VP8Io* io) { - for (dec->mb_y_ = 0; dec->mb_y_ < dec->br_mb_y_; ++dec->mb_y_) { - VP8BitReader* const token_br = - &dec->parts_[dec->mb_y_ & (dec->num_parts_ - 1)]; - VP8InitScanline(dec); - for (dec->mb_x_ = 0; 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."); - } - VP8ReconstructBlock(dec); - - // Store data and save block's filtering params - VP8StoreBlock(dec); - } - if (!VP8ProcessRow(dec, io)) { - return VP8SetError(dec, VP8_STATUS_USER_ABORT, "Output aborted."); - } - } - if (dec->use_threads_ && !WebPWorkerSync(&dec->worker_)) { - return 0; - } - - // Finish -#ifndef ONLY_KEYFRAME_CODE - if (!dec->update_proba_) { - dec->proba_ = dec->proba_saved_; - } -#endif - -#ifdef WEBP_EXPERIMENTAL_FEATURES - if (dec->layer_data_size_ > 0) { - if (!VP8DecodeLayer(dec)) { - return 0; - } - } -#endif - - 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; - } - if (dec->use_threads_) { - WebPWorkerEnd(&dec->worker_); - } - if (dec->mem_) { - free(dec->mem_); - } - dec->mem_ = NULL; - dec->mem_size_ = 0; - memset(&dec->br_, 0, sizeof(dec->br_)); - dec->ready_ = 0; -} - -//------------------------------------------------------------------------------ - -#if defined(__cplusplus) || defined(c_plusplus) -} // extern "C" -#endif |