diff options
Diffstat (limited to 'drivers/webpold/dec/vp8l.c')
| -rw-r--r-- | drivers/webpold/dec/vp8l.c | 1200 |
1 files changed, 0 insertions, 1200 deletions
diff --git a/drivers/webpold/dec/vp8l.c b/drivers/webpold/dec/vp8l.c deleted file mode 100644 index 897e4395c7..0000000000 --- a/drivers/webpold/dec/vp8l.c +++ /dev/null @@ -1,1200 +0,0 @@ -// Copyright 2012 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 -// -// Authors: Vikas Arora (vikaas.arora@gmail.com) -// Jyrki Alakuijala (jyrki@google.com) - -#include <stdio.h> -#include <stdlib.h> -#include "./vp8li.h" -#include "../dsp/lossless.h" -#include "../dsp/yuv.h" -#include "../utils/huffman.h" -#include "../utils/utils.h" - -#if defined(__cplusplus) || defined(c_plusplus) -extern "C" { -#endif - -#define NUM_ARGB_CACHE_ROWS 16 - -static const int kCodeLengthLiterals = 16; -static const int kCodeLengthRepeatCode = 16; -static const int kCodeLengthExtraBits[3] = { 2, 3, 7 }; -static const int kCodeLengthRepeatOffsets[3] = { 3, 3, 11 }; - -// ----------------------------------------------------------------------------- -// Five Huffman codes are used at each meta code: -// 1. green + length prefix codes + color cache codes, -// 2. alpha, -// 3. red, -// 4. blue, and, -// 5. distance prefix codes. -typedef enum { - GREEN = 0, - RED = 1, - BLUE = 2, - ALPHA = 3, - DIST = 4 -} HuffIndex; - -static const uint16_t kAlphabetSize[HUFFMAN_CODES_PER_META_CODE] = { - NUM_LITERAL_CODES + NUM_LENGTH_CODES, - NUM_LITERAL_CODES, NUM_LITERAL_CODES, NUM_LITERAL_CODES, - NUM_DISTANCE_CODES -}; - - -#define NUM_CODE_LENGTH_CODES 19 -static const uint8_t kCodeLengthCodeOrder[NUM_CODE_LENGTH_CODES] = { - 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 -}; - -#define CODE_TO_PLANE_CODES 120 -static const uint8_t code_to_plane_lut[CODE_TO_PLANE_CODES] = { - 0x18, 0x07, 0x17, 0x19, 0x28, 0x06, 0x27, 0x29, 0x16, 0x1a, - 0x26, 0x2a, 0x38, 0x05, 0x37, 0x39, 0x15, 0x1b, 0x36, 0x3a, - 0x25, 0x2b, 0x48, 0x04, 0x47, 0x49, 0x14, 0x1c, 0x35, 0x3b, - 0x46, 0x4a, 0x24, 0x2c, 0x58, 0x45, 0x4b, 0x34, 0x3c, 0x03, - 0x57, 0x59, 0x13, 0x1d, 0x56, 0x5a, 0x23, 0x2d, 0x44, 0x4c, - 0x55, 0x5b, 0x33, 0x3d, 0x68, 0x02, 0x67, 0x69, 0x12, 0x1e, - 0x66, 0x6a, 0x22, 0x2e, 0x54, 0x5c, 0x43, 0x4d, 0x65, 0x6b, - 0x32, 0x3e, 0x78, 0x01, 0x77, 0x79, 0x53, 0x5d, 0x11, 0x1f, - 0x64, 0x6c, 0x42, 0x4e, 0x76, 0x7a, 0x21, 0x2f, 0x75, 0x7b, - 0x31, 0x3f, 0x63, 0x6d, 0x52, 0x5e, 0x00, 0x74, 0x7c, 0x41, - 0x4f, 0x10, 0x20, 0x62, 0x6e, 0x30, 0x73, 0x7d, 0x51, 0x5f, - 0x40, 0x72, 0x7e, 0x61, 0x6f, 0x50, 0x71, 0x7f, 0x60, 0x70 -}; - -static int DecodeImageStream(int xsize, int ysize, - int is_level0, - VP8LDecoder* const dec, - uint32_t** const decoded_data); - -//------------------------------------------------------------------------------ - -int VP8LCheckSignature(const uint8_t* const data, size_t size) { - return (size >= 1) && (data[0] == VP8L_MAGIC_BYTE); -} - -static int ReadImageInfo(VP8LBitReader* const br, - int* const width, int* const height, - int* const has_alpha) { - const uint8_t signature = VP8LReadBits(br, 8); - if (!VP8LCheckSignature(&signature, 1)) { - return 0; - } - *width = VP8LReadBits(br, VP8L_IMAGE_SIZE_BITS) + 1; - *height = VP8LReadBits(br, VP8L_IMAGE_SIZE_BITS) + 1; - *has_alpha = VP8LReadBits(br, 1); - VP8LReadBits(br, VP8L_VERSION_BITS); // Read/ignore the version number. - return 1; -} - -int VP8LGetInfo(const uint8_t* data, size_t data_size, - int* const width, int* const height, int* const has_alpha) { - if (data == NULL || data_size < VP8L_FRAME_HEADER_SIZE) { - return 0; // not enough data - } else { - int w, h, a; - VP8LBitReader br; - VP8LInitBitReader(&br, data, data_size); - if (!ReadImageInfo(&br, &w, &h, &a)) { - return 0; - } - if (width != NULL) *width = w; - if (height != NULL) *height = h; - if (has_alpha != NULL) *has_alpha = a; - return 1; - } -} - -//------------------------------------------------------------------------------ - -static WEBP_INLINE int GetCopyDistance(int distance_symbol, - VP8LBitReader* const br) { - int extra_bits, offset; - if (distance_symbol < 4) { - return distance_symbol + 1; - } - extra_bits = (distance_symbol - 2) >> 1; - offset = (2 + (distance_symbol & 1)) << extra_bits; - return offset + VP8LReadBits(br, extra_bits) + 1; -} - -static WEBP_INLINE int GetCopyLength(int length_symbol, - VP8LBitReader* const br) { - // Length and distance prefixes are encoded the same way. - return GetCopyDistance(length_symbol, br); -} - -static WEBP_INLINE int PlaneCodeToDistance(int xsize, int plane_code) { - if (plane_code > CODE_TO_PLANE_CODES) { - return plane_code - CODE_TO_PLANE_CODES; - } else { - const int dist_code = code_to_plane_lut[plane_code - 1]; - const int yoffset = dist_code >> 4; - const int xoffset = 8 - (dist_code & 0xf); - const int dist = yoffset * xsize + xoffset; - return (dist >= 1) ? dist : 1; - } -} - -//------------------------------------------------------------------------------ -// Decodes the next Huffman code from bit-stream. -// FillBitWindow(br) needs to be called at minimum every second call -// to ReadSymbolUnsafe. -static int ReadSymbolUnsafe(const HuffmanTree* tree, VP8LBitReader* const br) { - const HuffmanTreeNode* node = tree->root_; - assert(node != NULL); - while (!HuffmanTreeNodeIsLeaf(node)) { - node = HuffmanTreeNextNode(node, VP8LReadOneBitUnsafe(br)); - } - return node->symbol_; -} - -static WEBP_INLINE int ReadSymbol(const HuffmanTree* tree, - VP8LBitReader* const br) { - const int read_safe = (br->pos_ + 8 > br->len_); - if (!read_safe) { - return ReadSymbolUnsafe(tree, br); - } else { - const HuffmanTreeNode* node = tree->root_; - assert(node != NULL); - while (!HuffmanTreeNodeIsLeaf(node)) { - node = HuffmanTreeNextNode(node, VP8LReadOneBit(br)); - } - return node->symbol_; - } -} - -static int ReadHuffmanCodeLengths( - VP8LDecoder* const dec, const int* const code_length_code_lengths, - int num_symbols, int* const code_lengths) { - int ok = 0; - VP8LBitReader* const br = &dec->br_; - int symbol; - int max_symbol; - int prev_code_len = DEFAULT_CODE_LENGTH; - HuffmanTree tree; - - if (!HuffmanTreeBuildImplicit(&tree, code_length_code_lengths, - NUM_CODE_LENGTH_CODES)) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; - } - - if (VP8LReadBits(br, 1)) { // use length - const int length_nbits = 2 + 2 * VP8LReadBits(br, 3); - max_symbol = 2 + VP8LReadBits(br, length_nbits); - if (max_symbol > num_symbols) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } - } else { - max_symbol = num_symbols; - } - - symbol = 0; - while (symbol < num_symbols) { - int code_len; - if (max_symbol-- == 0) break; - VP8LFillBitWindow(br); - code_len = ReadSymbol(&tree, br); - if (code_len < kCodeLengthLiterals) { - code_lengths[symbol++] = code_len; - if (code_len != 0) prev_code_len = code_len; - } else { - const int use_prev = (code_len == kCodeLengthRepeatCode); - const int slot = code_len - kCodeLengthLiterals; - const int extra_bits = kCodeLengthExtraBits[slot]; - const int repeat_offset = kCodeLengthRepeatOffsets[slot]; - int repeat = VP8LReadBits(br, extra_bits) + repeat_offset; - if (symbol + repeat > num_symbols) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } else { - const int length = use_prev ? prev_code_len : 0; - while (repeat-- > 0) code_lengths[symbol++] = length; - } - } - } - ok = 1; - - End: - HuffmanTreeRelease(&tree); - return ok; -} - -static int ReadHuffmanCode(int alphabet_size, VP8LDecoder* const dec, - HuffmanTree* const tree) { - int ok = 0; - VP8LBitReader* const br = &dec->br_; - const int simple_code = VP8LReadBits(br, 1); - - if (simple_code) { // Read symbols, codes & code lengths directly. - int symbols[2]; - int codes[2]; - int code_lengths[2]; - const int num_symbols = VP8LReadBits(br, 1) + 1; - const int first_symbol_len_code = VP8LReadBits(br, 1); - // The first code is either 1 bit or 8 bit code. - symbols[0] = VP8LReadBits(br, (first_symbol_len_code == 0) ? 1 : 8); - codes[0] = 0; - code_lengths[0] = num_symbols - 1; - // The second code (if present), is always 8 bit long. - if (num_symbols == 2) { - symbols[1] = VP8LReadBits(br, 8); - codes[1] = 1; - code_lengths[1] = num_symbols - 1; - } - ok = HuffmanTreeBuildExplicit(tree, code_lengths, codes, symbols, - alphabet_size, num_symbols); - } else { // Decode Huffman-coded code lengths. - int* code_lengths = NULL; - int i; - int code_length_code_lengths[NUM_CODE_LENGTH_CODES] = { 0 }; - const int num_codes = VP8LReadBits(br, 4) + 4; - if (num_codes > NUM_CODE_LENGTH_CODES) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; - } - - code_lengths = - (int*)WebPSafeCalloc((uint64_t)alphabet_size, sizeof(*code_lengths)); - if (code_lengths == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - - for (i = 0; i < num_codes; ++i) { - code_length_code_lengths[kCodeLengthCodeOrder[i]] = VP8LReadBits(br, 3); - } - ok = ReadHuffmanCodeLengths(dec, code_length_code_lengths, alphabet_size, - code_lengths); - if (ok) { - ok = HuffmanTreeBuildImplicit(tree, code_lengths, alphabet_size); - } - free(code_lengths); - } - ok = ok && !br->error_; - if (!ok) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - return 0; - } - return 1; -} - -static void DeleteHtreeGroups(HTreeGroup* htree_groups, int num_htree_groups) { - if (htree_groups != NULL) { - int i, j; - for (i = 0; i < num_htree_groups; ++i) { - HuffmanTree* const htrees = htree_groups[i].htrees_; - for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; ++j) { - HuffmanTreeRelease(&htrees[j]); - } - } - free(htree_groups); - } -} - -static int ReadHuffmanCodes(VP8LDecoder* const dec, int xsize, int ysize, - int color_cache_bits, int allow_recursion) { - int i, j; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - uint32_t* huffman_image = NULL; - HTreeGroup* htree_groups = NULL; - int num_htree_groups = 1; - - if (allow_recursion && VP8LReadBits(br, 1)) { - // use meta Huffman codes. - const int huffman_precision = VP8LReadBits(br, 3) + 2; - const int huffman_xsize = VP8LSubSampleSize(xsize, huffman_precision); - const int huffman_ysize = VP8LSubSampleSize(ysize, huffman_precision); - const int huffman_pixs = huffman_xsize * huffman_ysize; - if (!DecodeImageStream(huffman_xsize, huffman_ysize, 0, dec, - &huffman_image)) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto Error; - } - hdr->huffman_subsample_bits_ = huffman_precision; - for (i = 0; i < huffman_pixs; ++i) { - // The huffman data is stored in red and green bytes. - const int index = (huffman_image[i] >> 8) & 0xffff; - huffman_image[i] = index; - if (index >= num_htree_groups) { - num_htree_groups = index + 1; - } - } - } - - if (br->error_) goto Error; - - assert(num_htree_groups <= 0x10000); - htree_groups = - (HTreeGroup*)WebPSafeCalloc((uint64_t)num_htree_groups, - sizeof(*htree_groups)); - if (htree_groups == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - goto Error; - } - - for (i = 0; i < num_htree_groups; ++i) { - HuffmanTree* const htrees = htree_groups[i].htrees_; - for (j = 0; j < HUFFMAN_CODES_PER_META_CODE; ++j) { - int alphabet_size = kAlphabetSize[j]; - if (j == 0 && color_cache_bits > 0) { - alphabet_size += 1 << color_cache_bits; - } - if (!ReadHuffmanCode(alphabet_size, dec, htrees + j)) goto Error; - } - } - - // All OK. Finalize pointers and return. - hdr->huffman_image_ = huffman_image; - hdr->num_htree_groups_ = num_htree_groups; - hdr->htree_groups_ = htree_groups; - return 1; - - Error: - free(huffman_image); - DeleteHtreeGroups(htree_groups, num_htree_groups); - return 0; -} - -//------------------------------------------------------------------------------ -// Scaling. - -static int AllocateAndInitRescaler(VP8LDecoder* const dec, VP8Io* const io) { - const int num_channels = 4; - const int in_width = io->mb_w; - const int out_width = io->scaled_width; - const int in_height = io->mb_h; - const int out_height = io->scaled_height; - const uint64_t work_size = 2 * num_channels * (uint64_t)out_width; - int32_t* work; // Rescaler work area. - const uint64_t scaled_data_size = num_channels * (uint64_t)out_width; - uint32_t* scaled_data; // Temporary storage for scaled BGRA data. - const uint64_t memory_size = sizeof(*dec->rescaler) + - work_size * sizeof(*work) + - scaled_data_size * sizeof(*scaled_data); - uint8_t* memory = (uint8_t*)WebPSafeCalloc(memory_size, sizeof(*memory)); - if (memory == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - assert(dec->rescaler_memory == NULL); - dec->rescaler_memory = memory; - - dec->rescaler = (WebPRescaler*)memory; - memory += sizeof(*dec->rescaler); - work = (int32_t*)memory; - memory += work_size * sizeof(*work); - scaled_data = (uint32_t*)memory; - - WebPRescalerInit(dec->rescaler, in_width, in_height, (uint8_t*)scaled_data, - out_width, out_height, 0, num_channels, - in_width, out_width, in_height, out_height, work); - return 1; -} - -//------------------------------------------------------------------------------ -// Export to ARGB - -// We have special "export" function since we need to convert from BGRA -static int Export(WebPRescaler* const rescaler, WEBP_CSP_MODE colorspace, - int rgba_stride, uint8_t* const rgba) { - const uint32_t* const src = (const uint32_t*)rescaler->dst; - const int dst_width = rescaler->dst_width; - int num_lines_out = 0; - while (WebPRescalerHasPendingOutput(rescaler)) { - uint8_t* const dst = rgba + num_lines_out * rgba_stride; - WebPRescalerExportRow(rescaler); - VP8LConvertFromBGRA(src, dst_width, colorspace, dst); - ++num_lines_out; - } - return num_lines_out; -} - -// Emit scaled rows. -static int EmitRescaledRows(const VP8LDecoder* const dec, - const uint32_t* const data, int in_stride, int mb_h, - uint8_t* const out, int out_stride) { - const WEBP_CSP_MODE colorspace = dec->output_->colorspace; - const uint8_t* const in = (const uint8_t*)data; - int num_lines_in = 0; - int num_lines_out = 0; - while (num_lines_in < mb_h) { - const uint8_t* const row_in = in + num_lines_in * in_stride; - uint8_t* const row_out = out + num_lines_out * out_stride; - num_lines_in += WebPRescalerImport(dec->rescaler, mb_h - num_lines_in, - row_in, in_stride); - num_lines_out += Export(dec->rescaler, colorspace, out_stride, row_out); - } - return num_lines_out; -} - -// Emit rows without any scaling. -static int EmitRows(WEBP_CSP_MODE colorspace, - const uint32_t* const data, int in_stride, - int mb_w, int mb_h, - uint8_t* const out, int out_stride) { - int lines = mb_h; - const uint8_t* row_in = (const uint8_t*)data; - uint8_t* row_out = out; - while (lines-- > 0) { - VP8LConvertFromBGRA((const uint32_t*)row_in, mb_w, colorspace, row_out); - row_in += in_stride; - row_out += out_stride; - } - return mb_h; // Num rows out == num rows in. -} - -//------------------------------------------------------------------------------ -// Export to YUVA - -static void ConvertToYUVA(const uint32_t* const src, int width, int y_pos, - const WebPDecBuffer* const output) { - const WebPYUVABuffer* const buf = &output->u.YUVA; - // first, the luma plane - { - int i; - uint8_t* const y = buf->y + y_pos * buf->y_stride; - for (i = 0; i < width; ++i) { - const uint32_t p = src[i]; - y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >> 0) & 0xff); - } - } - - // then U/V planes - { - uint8_t* const u = buf->u + (y_pos >> 1) * buf->u_stride; - uint8_t* const v = buf->v + (y_pos >> 1) * buf->v_stride; - const int uv_width = width >> 1; - int i; - for (i = 0; i < uv_width; ++i) { - const uint32_t v0 = src[2 * i + 0]; - const uint32_t v1 = src[2 * i + 1]; - // VP8RGBToU/V expects four accumulated pixels. Hence we need to - // scale r/g/b value by a factor 2. We just shift v0/v1 one bit less. - const int r = ((v0 >> 15) & 0x1fe) + ((v1 >> 15) & 0x1fe); - const int g = ((v0 >> 7) & 0x1fe) + ((v1 >> 7) & 0x1fe); - const int b = ((v0 << 1) & 0x1fe) + ((v1 << 1) & 0x1fe); - if (!(y_pos & 1)) { // even lines: store values - u[i] = VP8RGBToU(r, g, b); - v[i] = VP8RGBToV(r, g, b); - } else { // odd lines: average with previous values - const int tmp_u = VP8RGBToU(r, g, b); - const int tmp_v = VP8RGBToV(r, g, b); - // Approximated average-of-four. But it's an acceptable diff. - u[i] = (u[i] + tmp_u + 1) >> 1; - v[i] = (v[i] + tmp_v + 1) >> 1; - } - } - if (width & 1) { // last pixel - const uint32_t v0 = src[2 * i + 0]; - const int r = (v0 >> 14) & 0x3fc; - const int g = (v0 >> 6) & 0x3fc; - const int b = (v0 << 2) & 0x3fc; - if (!(y_pos & 1)) { // even lines - u[i] = VP8RGBToU(r, g, b); - v[i] = VP8RGBToV(r, g, b); - } else { // odd lines (note: we could just skip this) - const int tmp_u = VP8RGBToU(r, g, b); - const int tmp_v = VP8RGBToV(r, g, b); - u[i] = (u[i] + tmp_u + 1) >> 1; - v[i] = (v[i] + tmp_v + 1) >> 1; - } - } - } - // Lastly, store alpha if needed. - if (buf->a != NULL) { - int i; - uint8_t* const a = buf->a + y_pos * buf->a_stride; - for (i = 0; i < width; ++i) a[i] = (src[i] >> 24); - } -} - -static int ExportYUVA(const VP8LDecoder* const dec, int y_pos) { - WebPRescaler* const rescaler = dec->rescaler; - const uint32_t* const src = (const uint32_t*)rescaler->dst; - const int dst_width = rescaler->dst_width; - int num_lines_out = 0; - while (WebPRescalerHasPendingOutput(rescaler)) { - WebPRescalerExportRow(rescaler); - ConvertToYUVA(src, dst_width, y_pos, dec->output_); - ++y_pos; - ++num_lines_out; - } - return num_lines_out; -} - -static int EmitRescaledRowsYUVA(const VP8LDecoder* const dec, - const uint32_t* const data, - int in_stride, int mb_h) { - const uint8_t* const in = (const uint8_t*)data; - int num_lines_in = 0; - int y_pos = dec->last_out_row_; - while (num_lines_in < mb_h) { - const uint8_t* const row_in = in + num_lines_in * in_stride; - num_lines_in += WebPRescalerImport(dec->rescaler, mb_h - num_lines_in, - row_in, in_stride); - y_pos += ExportYUVA(dec, y_pos); - } - return y_pos; -} - -static int EmitRowsYUVA(const VP8LDecoder* const dec, - const uint32_t* const data, int in_stride, - int mb_w, int num_rows) { - int y_pos = dec->last_out_row_; - const uint8_t* row_in = (const uint8_t*)data; - while (num_rows-- > 0) { - ConvertToYUVA((const uint32_t*)row_in, mb_w, y_pos, dec->output_); - row_in += in_stride; - ++y_pos; - } - return y_pos; -} - -//------------------------------------------------------------------------------ -// Cropping. - -// Sets io->mb_y, io->mb_h & io->mb_w according to start row, end row and -// crop options. Also updates the input data pointer, so that it points to the -// start of the cropped window. -// Note that 'pixel_stride' is in units of 'uint32_t' (and not 'bytes). -// Returns true if the crop window is not empty. -static int SetCropWindow(VP8Io* const io, int y_start, int y_end, - const uint32_t** const in_data, int pixel_stride) { - assert(y_start < y_end); - assert(io->crop_left < io->crop_right); - if (y_end > io->crop_bottom) { - y_end = io->crop_bottom; // make sure we don't overflow on last row. - } - if (y_start < io->crop_top) { - const int delta = io->crop_top - y_start; - y_start = io->crop_top; - *in_data += pixel_stride * delta; - } - if (y_start >= y_end) return 0; // Crop window is empty. - - *in_data += io->crop_left; - - io->mb_y = y_start - io->crop_top; - io->mb_w = io->crop_right - io->crop_left; - io->mb_h = y_end - y_start; - return 1; // Non-empty crop window. -} - -//------------------------------------------------------------------------------ - -static WEBP_INLINE int GetMetaIndex( - const uint32_t* const image, int xsize, int bits, int x, int y) { - if (bits == 0) return 0; - return image[xsize * (y >> bits) + (x >> bits)]; -} - -static WEBP_INLINE HTreeGroup* GetHtreeGroupForPos(VP8LMetadata* const hdr, - int x, int y) { - const int meta_index = GetMetaIndex(hdr->huffman_image_, hdr->huffman_xsize_, - hdr->huffman_subsample_bits_, x, y); - assert(meta_index < hdr->num_htree_groups_); - return hdr->htree_groups_ + meta_index; -} - -//------------------------------------------------------------------------------ -// Main loop, with custom row-processing function - -typedef void (*ProcessRowsFunc)(VP8LDecoder* const dec, int row); - -static void ApplyInverseTransforms(VP8LDecoder* const dec, int num_rows, - const uint32_t* const rows) { - int n = dec->next_transform_; - const int cache_pixs = dec->width_ * num_rows; - const int start_row = dec->last_row_; - const int end_row = start_row + num_rows; - const uint32_t* rows_in = rows; - uint32_t* const rows_out = dec->argb_cache_; - - // Inverse transforms. - // TODO: most transforms only need to operate on the cropped region only. - memcpy(rows_out, rows_in, cache_pixs * sizeof(*rows_out)); - while (n-- > 0) { - VP8LTransform* const transform = &dec->transforms_[n]; - VP8LInverseTransform(transform, start_row, end_row, rows_in, rows_out); - rows_in = rows_out; - } -} - -// Processes (transforms, scales & color-converts) the rows decoded after the -// last call. -static void ProcessRows(VP8LDecoder* const dec, int row) { - const uint32_t* const rows = dec->argb_ + dec->width_ * dec->last_row_; - const int num_rows = row - dec->last_row_; - - if (num_rows <= 0) return; // Nothing to be done. - ApplyInverseTransforms(dec, num_rows, rows); - - // Emit output. - { - VP8Io* const io = dec->io_; - const uint32_t* rows_data = dec->argb_cache_; - if (!SetCropWindow(io, dec->last_row_, row, &rows_data, io->width)) { - // Nothing to output (this time). - } else { - const WebPDecBuffer* const output = dec->output_; - const int in_stride = io->width * sizeof(*rows_data); - if (output->colorspace < MODE_YUV) { // convert to RGBA - const WebPRGBABuffer* const buf = &output->u.RGBA; - uint8_t* const rgba = buf->rgba + dec->last_out_row_ * buf->stride; - const int num_rows_out = io->use_scaling ? - EmitRescaledRows(dec, rows_data, in_stride, io->mb_h, - rgba, buf->stride) : - EmitRows(output->colorspace, rows_data, in_stride, - io->mb_w, io->mb_h, rgba, buf->stride); - // Update 'last_out_row_'. - dec->last_out_row_ += num_rows_out; - } else { // convert to YUVA - dec->last_out_row_ = io->use_scaling ? - EmitRescaledRowsYUVA(dec, rows_data, in_stride, io->mb_h) : - EmitRowsYUVA(dec, rows_data, in_stride, io->mb_w, io->mb_h); - } - assert(dec->last_out_row_ <= output->height); - } - } - - // Update 'last_row_'. - dec->last_row_ = row; - assert(dec->last_row_ <= dec->height_); -} - -static int DecodeImageData(VP8LDecoder* const dec, - uint32_t* const data, int width, int height, - ProcessRowsFunc process_func) { - int ok = 1; - int col = 0, row = 0; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - HTreeGroup* htree_group = hdr->htree_groups_; - uint32_t* src = data; - uint32_t* last_cached = data; - uint32_t* const src_end = data + width * height; - const int len_code_limit = NUM_LITERAL_CODES + NUM_LENGTH_CODES; - const int color_cache_limit = len_code_limit + hdr->color_cache_size_; - VP8LColorCache* const color_cache = - (hdr->color_cache_size_ > 0) ? &hdr->color_cache_ : NULL; - const int mask = hdr->huffman_mask_; - - assert(htree_group != NULL); - - while (!br->eos_ && src < src_end) { - int code; - // Only update when changing tile. Note we could use the following test: - // if "((((prev_col ^ col) | prev_row ^ row)) > mask)" -> tile changed - // but that's actually slower and requires storing the previous col/row - if ((col & mask) == 0) { - htree_group = GetHtreeGroupForPos(hdr, col, row); - } - VP8LFillBitWindow(br); - code = ReadSymbol(&htree_group->htrees_[GREEN], br); - if (code < NUM_LITERAL_CODES) { // Literal. - int red, green, blue, alpha; - red = ReadSymbol(&htree_group->htrees_[RED], br); - green = code; - VP8LFillBitWindow(br); - blue = ReadSymbol(&htree_group->htrees_[BLUE], br); - alpha = ReadSymbol(&htree_group->htrees_[ALPHA], br); - *src = (alpha << 24) + (red << 16) + (green << 8) + blue; - AdvanceByOne: - ++src; - ++col; - if (col >= width) { - col = 0; - ++row; - if ((process_func != NULL) && (row % NUM_ARGB_CACHE_ROWS == 0)) { - process_func(dec, row); - } - if (color_cache != NULL) { - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - } - } - } else if (code < len_code_limit) { // Backward reference - int dist_code, dist; - const int length_sym = code - NUM_LITERAL_CODES; - const int length = GetCopyLength(length_sym, br); - const int dist_symbol = ReadSymbol(&htree_group->htrees_[DIST], br); - VP8LFillBitWindow(br); - dist_code = GetCopyDistance(dist_symbol, br); - dist = PlaneCodeToDistance(width, dist_code); - if (src - data < dist || src_end - src < length) { - ok = 0; - goto End; - } - { - int i; - for (i = 0; i < length; ++i) src[i] = src[i - dist]; - src += length; - } - col += length; - while (col >= width) { - col -= width; - ++row; - if ((process_func != NULL) && (row % NUM_ARGB_CACHE_ROWS == 0)) { - process_func(dec, row); - } - } - if (src < src_end) { - htree_group = GetHtreeGroupForPos(hdr, col, row); - if (color_cache != NULL) { - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - } - } - } else if (code < color_cache_limit) { // Color cache. - const int key = code - len_code_limit; - assert(color_cache != NULL); - while (last_cached < src) { - VP8LColorCacheInsert(color_cache, *last_cached++); - } - *src = VP8LColorCacheLookup(color_cache, key); - goto AdvanceByOne; - } else { // Not reached. - ok = 0; - goto End; - } - ok = !br->error_; - if (!ok) goto End; - } - // Process the remaining rows corresponding to last row-block. - if (process_func != NULL) process_func(dec, row); - - End: - if (br->error_ || !ok || (br->eos_ && src < src_end)) { - ok = 0; - dec->status_ = (!br->eos_) ? - VP8_STATUS_BITSTREAM_ERROR : VP8_STATUS_SUSPENDED; - } else if (src == src_end) { - dec->state_ = READ_DATA; - } - - return ok; -} - -// ----------------------------------------------------------------------------- -// VP8LTransform - -static void ClearTransform(VP8LTransform* const transform) { - free(transform->data_); - transform->data_ = NULL; -} - -// For security reason, we need to remap the color map to span -// the total possible bundled values, and not just the num_colors. -static int ExpandColorMap(int num_colors, VP8LTransform* const transform) { - int i; - const int final_num_colors = 1 << (8 >> transform->bits_); - uint32_t* const new_color_map = - (uint32_t*)WebPSafeMalloc((uint64_t)final_num_colors, - sizeof(*new_color_map)); - if (new_color_map == NULL) { - return 0; - } else { - uint8_t* const data = (uint8_t*)transform->data_; - uint8_t* const new_data = (uint8_t*)new_color_map; - new_color_map[0] = transform->data_[0]; - for (i = 4; i < 4 * num_colors; ++i) { - // Equivalent to AddPixelEq(), on a byte-basis. - new_data[i] = (data[i] + new_data[i - 4]) & 0xff; - } - for (; i < 4 * final_num_colors; ++i) - new_data[i] = 0; // black tail. - free(transform->data_); - transform->data_ = new_color_map; - } - return 1; -} - -static int ReadTransform(int* const xsize, int const* ysize, - VP8LDecoder* const dec) { - int ok = 1; - VP8LBitReader* const br = &dec->br_; - VP8LTransform* transform = &dec->transforms_[dec->next_transform_]; - const VP8LImageTransformType type = - (VP8LImageTransformType)VP8LReadBits(br, 2); - - // Each transform type can only be present once in the stream. - if (dec->transforms_seen_ & (1U << type)) { - return 0; // Already there, let's not accept the second same transform. - } - dec->transforms_seen_ |= (1U << type); - - transform->type_ = type; - transform->xsize_ = *xsize; - transform->ysize_ = *ysize; - transform->data_ = NULL; - ++dec->next_transform_; - assert(dec->next_transform_ <= NUM_TRANSFORMS); - - switch (type) { - case PREDICTOR_TRANSFORM: - case CROSS_COLOR_TRANSFORM: - transform->bits_ = VP8LReadBits(br, 3) + 2; - ok = DecodeImageStream(VP8LSubSampleSize(transform->xsize_, - transform->bits_), - VP8LSubSampleSize(transform->ysize_, - transform->bits_), - 0, dec, &transform->data_); - break; - case COLOR_INDEXING_TRANSFORM: { - const int num_colors = VP8LReadBits(br, 8) + 1; - const int bits = (num_colors > 16) ? 0 - : (num_colors > 4) ? 1 - : (num_colors > 2) ? 2 - : 3; - *xsize = VP8LSubSampleSize(transform->xsize_, bits); - transform->bits_ = bits; - ok = DecodeImageStream(num_colors, 1, 0, dec, &transform->data_); - ok = ok && ExpandColorMap(num_colors, transform); - break; - } - case SUBTRACT_GREEN: - break; - default: - assert(0); // can't happen - break; - } - - return ok; -} - -// ----------------------------------------------------------------------------- -// VP8LMetadata - -static void InitMetadata(VP8LMetadata* const hdr) { - assert(hdr); - memset(hdr, 0, sizeof(*hdr)); -} - -static void ClearMetadata(VP8LMetadata* const hdr) { - assert(hdr); - - free(hdr->huffman_image_); - DeleteHtreeGroups(hdr->htree_groups_, hdr->num_htree_groups_); - VP8LColorCacheClear(&hdr->color_cache_); - InitMetadata(hdr); -} - -// ----------------------------------------------------------------------------- -// VP8LDecoder - -VP8LDecoder* VP8LNew(void) { - VP8LDecoder* const dec = (VP8LDecoder*)calloc(1, sizeof(*dec)); - if (dec == NULL) return NULL; - dec->status_ = VP8_STATUS_OK; - dec->action_ = READ_DIM; - dec->state_ = READ_DIM; - return dec; -} - -void VP8LClear(VP8LDecoder* const dec) { - int i; - if (dec == NULL) return; - ClearMetadata(&dec->hdr_); - - free(dec->argb_); - dec->argb_ = NULL; - for (i = 0; i < dec->next_transform_; ++i) { - ClearTransform(&dec->transforms_[i]); - } - dec->next_transform_ = 0; - dec->transforms_seen_ = 0; - - free(dec->rescaler_memory); - dec->rescaler_memory = NULL; - - dec->output_ = NULL; // leave no trace behind -} - -void VP8LDelete(VP8LDecoder* const dec) { - if (dec != NULL) { - VP8LClear(dec); - free(dec); - } -} - -static void UpdateDecoder(VP8LDecoder* const dec, int width, int height) { - VP8LMetadata* const hdr = &dec->hdr_; - const int num_bits = hdr->huffman_subsample_bits_; - dec->width_ = width; - dec->height_ = height; - - hdr->huffman_xsize_ = VP8LSubSampleSize(width, num_bits); - hdr->huffman_mask_ = (num_bits == 0) ? ~0 : (1 << num_bits) - 1; -} - -static int DecodeImageStream(int xsize, int ysize, - int is_level0, - VP8LDecoder* const dec, - uint32_t** const decoded_data) { - int ok = 1; - int transform_xsize = xsize; - int transform_ysize = ysize; - VP8LBitReader* const br = &dec->br_; - VP8LMetadata* const hdr = &dec->hdr_; - uint32_t* data = NULL; - int color_cache_bits = 0; - - // Read the transforms (may recurse). - if (is_level0) { - while (ok && VP8LReadBits(br, 1)) { - ok = ReadTransform(&transform_xsize, &transform_ysize, dec); - } - } - - // Color cache - if (ok && VP8LReadBits(br, 1)) { - color_cache_bits = VP8LReadBits(br, 4); - ok = (color_cache_bits >= 1 && color_cache_bits <= MAX_CACHE_BITS); - if (!ok) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } - } - - // Read the Huffman codes (may recurse). - ok = ok && ReadHuffmanCodes(dec, transform_xsize, transform_ysize, - color_cache_bits, is_level0); - if (!ok) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto End; - } - - // Finish setting up the color-cache - if (color_cache_bits > 0) { - hdr->color_cache_size_ = 1 << color_cache_bits; - if (!VP8LColorCacheInit(&hdr->color_cache_, color_cache_bits)) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - ok = 0; - goto End; - } - } else { - hdr->color_cache_size_ = 0; - } - UpdateDecoder(dec, transform_xsize, transform_ysize); - - if (is_level0) { // level 0 complete - dec->state_ = READ_HDR; - goto End; - } - - { - const uint64_t total_size = (uint64_t)transform_xsize * transform_ysize; - data = (uint32_t*)WebPSafeMalloc(total_size, sizeof(*data)); - if (data == NULL) { - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - ok = 0; - goto End; - } - } - - // Use the Huffman trees to decode the LZ77 encoded data. - ok = DecodeImageData(dec, data, transform_xsize, transform_ysize, NULL); - ok = ok && !br->error_; - - End: - - if (!ok) { - free(data); - ClearMetadata(hdr); - // If not enough data (br.eos_) resulted in BIT_STREAM_ERROR, update the - // status appropriately. - if (dec->status_ == VP8_STATUS_BITSTREAM_ERROR && dec->br_.eos_) { - dec->status_ = VP8_STATUS_SUSPENDED; - } - } else { - if (decoded_data != NULL) { - *decoded_data = data; - } else { - // We allocate image data in this function only for transforms. At level 0 - // (that is: not the transforms), we shouldn't have allocated anything. - assert(data == NULL); - assert(is_level0); - } - if (!is_level0) ClearMetadata(hdr); // Clean up temporary data behind. - } - return ok; -} - -//------------------------------------------------------------------------------ -// Allocate dec->argb_ and dec->argb_cache_ using dec->width_ and dec->height_ - -static int AllocateARGBBuffers(VP8LDecoder* const dec, int final_width) { - const uint64_t num_pixels = (uint64_t)dec->width_ * dec->height_; - // Scratch buffer corresponding to top-prediction row for transforming the - // first row in the row-blocks. - const uint64_t cache_top_pixels = final_width; - // Scratch buffer for temporary BGRA storage. - const uint64_t cache_pixels = (uint64_t)final_width * NUM_ARGB_CACHE_ROWS; - const uint64_t total_num_pixels = - num_pixels + cache_top_pixels + cache_pixels; - - assert(dec->width_ <= final_width); - dec->argb_ = (uint32_t*)WebPSafeMalloc(total_num_pixels, sizeof(*dec->argb_)); - if (dec->argb_ == NULL) { - dec->argb_cache_ = NULL; // for sanity check - dec->status_ = VP8_STATUS_OUT_OF_MEMORY; - return 0; - } - dec->argb_cache_ = dec->argb_ + num_pixels + cache_top_pixels; - return 1; -} - -//------------------------------------------------------------------------------ -// Special row-processing that only stores the alpha data. - -static void ExtractAlphaRows(VP8LDecoder* const dec, int row) { - const int num_rows = row - dec->last_row_; - const uint32_t* const in = dec->argb_ + dec->width_ * dec->last_row_; - - if (num_rows <= 0) return; // Nothing to be done. - ApplyInverseTransforms(dec, num_rows, in); - - // Extract alpha (which is stored in the green plane). - { - const int width = dec->io_->width; // the final width (!= dec->width_) - const int cache_pixs = width * num_rows; - uint8_t* const dst = (uint8_t*)dec->io_->opaque + width * dec->last_row_; - const uint32_t* const src = dec->argb_cache_; - int i; - for (i = 0; i < cache_pixs; ++i) dst[i] = (src[i] >> 8) & 0xff; - } - - dec->last_row_ = dec->last_out_row_ = row; -} - -int VP8LDecodeAlphaImageStream(int width, int height, const uint8_t* const data, - size_t data_size, uint8_t* const output) { - VP8Io io; - int ok = 0; - VP8LDecoder* const dec = VP8LNew(); - if (dec == NULL) return 0; - - dec->width_ = width; - dec->height_ = height; - dec->io_ = &io; - - VP8InitIo(&io); - WebPInitCustomIo(NULL, &io); // Just a sanity Init. io won't be used. - io.opaque = output; - io.width = width; - io.height = height; - - dec->status_ = VP8_STATUS_OK; - VP8LInitBitReader(&dec->br_, data, data_size); - - dec->action_ = READ_HDR; - if (!DecodeImageStream(width, height, 1, dec, NULL)) goto Err; - - // Allocate output (note that dec->width_ may have changed here). - if (!AllocateARGBBuffers(dec, width)) goto Err; - - // Decode (with special row processing). - dec->action_ = READ_DATA; - ok = DecodeImageData(dec, dec->argb_, dec->width_, dec->height_, - ExtractAlphaRows); - - Err: - VP8LDelete(dec); - return ok; -} - -//------------------------------------------------------------------------------ - -int VP8LDecodeHeader(VP8LDecoder* const dec, VP8Io* const io) { - int width, height, has_alpha; - - if (dec == NULL) return 0; - if (io == NULL) { - dec->status_ = VP8_STATUS_INVALID_PARAM; - return 0; - } - - dec->io_ = io; - dec->status_ = VP8_STATUS_OK; - VP8LInitBitReader(&dec->br_, io->data, io->data_size); - if (!ReadImageInfo(&dec->br_, &width, &height, &has_alpha)) { - dec->status_ = VP8_STATUS_BITSTREAM_ERROR; - goto Error; - } - dec->state_ = READ_DIM; - io->width = width; - io->height = height; - - dec->action_ = READ_HDR; - if (!DecodeImageStream(width, height, 1, dec, NULL)) goto Error; - return 1; - - Error: - VP8LClear(dec); - assert(dec->status_ != VP8_STATUS_OK); - return 0; -} - -int VP8LDecodeImage(VP8LDecoder* const dec) { - VP8Io* io = NULL; - WebPDecParams* params = NULL; - - // Sanity checks. - if (dec == NULL) return 0; - - io = dec->io_; - assert(io != NULL); - params = (WebPDecParams*)io->opaque; - assert(params != NULL); - dec->output_ = params->output; - assert(dec->output_ != NULL); - - // Initialization. - if (!WebPIoInitFromOptions(params->options, io, MODE_BGRA)) { - dec->status_ = VP8_STATUS_INVALID_PARAM; - goto Err; - } - - if (!AllocateARGBBuffers(dec, io->width)) goto Err; - - if (io->use_scaling && !AllocateAndInitRescaler(dec, io)) goto Err; - - // Decode. - dec->action_ = READ_DATA; - if (!DecodeImageData(dec, dec->argb_, dec->width_, dec->height_, - ProcessRows)) { - goto Err; - } - - // Cleanup. - params->last_y = dec->last_out_row_; - VP8LClear(dec); - return 1; - - Err: - VP8LClear(dec); - assert(dec->status_ != VP8_STATUS_OK); - return 0; -} - -//------------------------------------------------------------------------------ - -#if defined(__cplusplus) || defined(c_plusplus) -} // extern "C" -#endif |