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enable lossless decoder

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import changes from experimental 5529a2e^
and enable build in autoconf and makefile.unix; windows will be treated
separately.

Change-Id: Ie2e177a99db63190b4cd647b3edee3b4e13719e9
This commit is contained in:
James Zern
2012-04-10 18:41:18 -07:00
parent b96efd7d50
commit f2623dbe58
8 changed files with 331 additions and 212 deletions
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43
src/dec/vp8.c
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@ -12,7 +12,9 @@
#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" {
@ -243,14 +245,11 @@ static int ParseFilterHeader(VP8BitReader* br, VP8Decoder* const dec) {
int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
const uint8_t* buf;
uint32_t buf_size;
const uint8_t* alpha_data_tmp;
uint32_t alpha_size_tmp;
uint32_t vp8_chunk_size;
uint32_t bytes_skipped;
VP8FrameHeader* frm_hdr;
VP8PictureHeader* pic_hdr;
VP8BitReader* br;
VP8StatusCode status;
WebPHeaderStructure headers;
if (dec == NULL) {
return 0;
@ -261,26 +260,44 @@ int VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io) {
"null VP8Io passed to VP8GetHeaders()");
}
buf = io->data;
buf_size = io->data_size;
headers.data = io->data;
headers.data_size = io->data_size;
// Process Pre-VP8 chunks.
status = WebPParseHeaders(&buf, &buf_size, &vp8_chunk_size, &bytes_skipped,
&alpha_data_tmp, &alpha_size_tmp);
status = WebPParseHeaders(&headers);
if (status != VP8_STATUS_OK) {
return VP8SetError(dec, status, "Incorrect/incomplete header.");
}
if (headers.is_lossless) {
int ok;
VP8LDecoder* const vp8l_decoder = &dec->vp8l_decoder_;
VP8LInitDecoder(vp8l_decoder);
vp8l_decoder->br_offset_ = headers.offset;
ok = VP8LDecodeHeader(vp8l_decoder, io);
if (!ok) {
VP8LClear(vp8l_decoder);
return VP8SetError(dec, vp8l_decoder->status_,
"Incorrect/incomplete header.");
} else {
dec->is_lossless_ = 1;
}
return ok;
}
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_ = alpha_data_tmp;
dec->alpha_data_size_ = alpha_size_tmp;
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.");
@ -724,6 +741,9 @@ int VP8Decode(VP8Decoder* const dec, VP8Io* const io) {
}
assert(dec->ready_);
// TODO: Implement lossless decoding. Error till then.
if (dec->is_lossless_) goto Error;
// Finish setting up the decoding parameter. Will call io->setup().
ok = (VP8EnterCritical(dec, io) == VP8_STATUS_OK);
if (ok) { // good to go.
@ -737,13 +757,14 @@ int VP8Decode(VP8Decoder* const dec, VP8Io* const io) {
ok &= VP8ExitCritical(dec, io);
}
Error:
if (!ok) {
VP8Clear(dec);
return 0;
}
dec->ready_ = 0;
return 1;
return ok;
}
void VP8Clear(VP8Decoder* const dec) {