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authorRémi Verschelde <rverschelde@gmail.com>2016-07-14 08:36:06 +0200
committerRémi Verschelde <rverschelde@gmail.com>2016-07-14 08:36:06 +0200
commit68fbb8f8ac5c11a751c455fa1c4465522e21713f (patch)
tree02ff025a90af82d9a2031d8b7b63ad6e540113ad /drivers/webpold/dec/alpha.c
parentb3cf4c73fcd51a893ed12dfea110151968e1a2e0 (diff)
Drop obsolete "webpold" backup of previous webp version
Fixes #5252
Diffstat (limited to 'drivers/webpold/dec/alpha.c')
-rw-r--r--drivers/webpold/dec/alpha.c140
1 files changed, 0 insertions, 140 deletions
diff --git a/drivers/webpold/dec/alpha.c b/drivers/webpold/dec/alpha.c
deleted file mode 100644
index d1095fa555..0000000000
--- a/drivers/webpold/dec/alpha.c
+++ /dev/null
@@ -1,140 +0,0 @@
-// Copyright 2011 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/
-// -----------------------------------------------------------------------------
-//
-// Alpha-plane decompression.
-//
-// Author: Skal (pascal.massimino@gmail.com)
-
-#include <stdlib.h>
-#include "./vp8i.h"
-#include "./vp8li.h"
-#include "../utils/filters.h"
-#include "../utils/quant_levels.h"
-#include "../format_constants.h"
-
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
-// TODO(skal): move to dsp/ ?
-static void CopyPlane(const uint8_t* src, int src_stride,
- uint8_t* dst, int dst_stride, int width, int height) {
- while (height-- > 0) {
- memcpy(dst, src, width);
- src += src_stride;
- dst += dst_stride;
- }
-}
-
-//------------------------------------------------------------------------------
-// Decodes the compressed data 'data' of size 'data_size' into the 'output'.
-// The 'output' buffer should be pre-allocated and must be of the same
-// dimension 'height'x'stride', as that of the image.
-//
-// Returns 1 on successfully decoding the compressed alpha and
-// 0 if either:
-// error in bit-stream header (invalid compression mode or filter), or
-// error returned by appropriate compression method.
-
-static int DecodeAlpha(const uint8_t* data, size_t data_size,
- int width, int height, int stride, uint8_t* output) {
- uint8_t* decoded_data = NULL;
- const size_t decoded_size = height * width;
- uint8_t* unfiltered_data = NULL;
- WEBP_FILTER_TYPE filter;
- int pre_processing;
- int rsrv;
- int ok = 0;
- int method;
-
- assert(width > 0 && height > 0 && stride >= width);
- assert(data != NULL && output != NULL);
-
- if (data_size <= ALPHA_HEADER_LEN) {
- return 0;
- }
-
- method = (data[0] >> 0) & 0x03;
- filter = (data[0] >> 2) & 0x03;
- pre_processing = (data[0] >> 4) & 0x03;
- rsrv = (data[0] >> 6) & 0x03;
- if (method < ALPHA_NO_COMPRESSION ||
- method > ALPHA_LOSSLESS_COMPRESSION ||
- filter >= WEBP_FILTER_LAST ||
- pre_processing > ALPHA_PREPROCESSED_LEVELS ||
- rsrv != 0) {
- return 0;
- }
-
- if (method == ALPHA_NO_COMPRESSION) {
- ok = (data_size >= decoded_size);
- decoded_data = (uint8_t*)data + ALPHA_HEADER_LEN;
- } else {
- decoded_data = (uint8_t*)malloc(decoded_size);
- if (decoded_data == NULL) return 0;
- ok = VP8LDecodeAlphaImageStream(width, height,
- data + ALPHA_HEADER_LEN,
- data_size - ALPHA_HEADER_LEN,
- decoded_data);
- }
-
- if (ok) {
- WebPFilterFunc unfilter_func = WebPUnfilters[filter];
- if (unfilter_func != NULL) {
- unfiltered_data = (uint8_t*)malloc(decoded_size);
- if (unfiltered_data == NULL) {
- ok = 0;
- goto Error;
- }
- // TODO(vikas): Implement on-the-fly decoding & filter mechanism to decode
- // and apply filter per image-row.
- unfilter_func(decoded_data, width, height, 1, width, unfiltered_data);
- // Construct raw_data (height x stride) from alpha data (height x width).
- CopyPlane(unfiltered_data, width, output, stride, width, height);
- free(unfiltered_data);
- } else {
- // Construct raw_data (height x stride) from alpha data (height x width).
- CopyPlane(decoded_data, width, output, stride, width, height);
- }
- if (pre_processing == ALPHA_PREPROCESSED_LEVELS) {
- ok = DequantizeLevels(decoded_data, width, height);
- }
- }
-
- Error:
- if (method != ALPHA_NO_COMPRESSION) {
- free(decoded_data);
- }
- return ok;
-}
-
-//------------------------------------------------------------------------------
-
-const uint8_t* VP8DecompressAlphaRows(VP8Decoder* const dec,
- int row, int num_rows) {
- const int stride = dec->pic_hdr_.width_;
-
- if (row < 0 || num_rows < 0 || row + num_rows > dec->pic_hdr_.height_) {
- return NULL; // sanity check.
- }
-
- if (row == 0) {
- // Decode everything during the first call.
- if (!DecodeAlpha(dec->alpha_data_, (size_t)dec->alpha_data_size_,
- dec->pic_hdr_.width_, dec->pic_hdr_.height_, stride,
- dec->alpha_plane_)) {
- return NULL; // Error.
- }
- }
-
- // Return a pointer to the current decoded row.
- return dec->alpha_plane_ + row * stride;
-}
-
-#if defined(__cplusplus) || defined(c_plusplus)
-} // extern "C"
-#endif