VP8LSetBitPos: remove the eos_ setting
This code is ultra-critical for lossless decoding, especially on ARM. The extra call VP8LIsEndOfStream() was causing unnecessary slow-down. Now, we check for bitstream-end separately in the main loop. Change-Id: I739b5d74cc29578e2b712ba99b544fd995ef0e0d
This commit is contained in:
parent
027151ca6c
commit
16be192f47
@ -1012,12 +1012,13 @@ static int DecodeAlphaData(VP8LDecoder* const dec, uint8_t* const data,
|
||||
ok = 0;
|
||||
goto End;
|
||||
}
|
||||
assert(br->eos_ == VP8LIsEndOfStream(br));
|
||||
br->eos_ = VP8LIsEndOfStream(br);
|
||||
}
|
||||
// Process the remaining rows corresponding to last row-block.
|
||||
ExtractPalettedAlphaRows(dec, row > last_row ? last_row : row);
|
||||
|
||||
End:
|
||||
br->eos_ = VP8LIsEndOfStream(br);
|
||||
if (!ok || (br->eos_ && pos < end)) {
|
||||
ok = 0;
|
||||
dec->status_ = br->eos_ ? VP8_STATUS_SUSPENDED
|
||||
@ -1094,7 +1095,7 @@ static int DecodeImageData(VP8LDecoder* const dec, uint32_t* const data,
|
||||
} else {
|
||||
code = ReadSymbol(htree_group->htrees[GREEN], br);
|
||||
}
|
||||
if (br->eos_) break; // early out
|
||||
if (VP8LIsEndOfStream(br)) break;
|
||||
if (code < NUM_LITERAL_CODES) { // Literal
|
||||
if (htree_group->is_trivial_literal) {
|
||||
*src = htree_group->literal_arb | (code << 8);
|
||||
@ -1104,7 +1105,7 @@ static int DecodeImageData(VP8LDecoder* const dec, uint32_t* const data,
|
||||
VP8LFillBitWindow(br);
|
||||
blue = ReadSymbol(htree_group->htrees[BLUE], br);
|
||||
alpha = ReadSymbol(htree_group->htrees[ALPHA], br);
|
||||
if (br->eos_) break;
|
||||
if (VP8LIsEndOfStream(br)) break;
|
||||
*src = ((uint32_t)alpha << 24) | (red << 16) | (code << 8) | blue;
|
||||
}
|
||||
AdvanceByOne:
|
||||
@ -1132,7 +1133,7 @@ static int DecodeImageData(VP8LDecoder* const dec, uint32_t* const data,
|
||||
VP8LFillBitWindow(br);
|
||||
dist_code = GetCopyDistance(dist_symbol, br);
|
||||
dist = PlaneCodeToDistance(width, dist_code);
|
||||
if (br->eos_) break;
|
||||
if (VP8LIsEndOfStream(br)) break;
|
||||
if (src - data < (ptrdiff_t)dist || src_end - src < (ptrdiff_t)length) {
|
||||
goto Error;
|
||||
} else {
|
||||
@ -1169,9 +1170,9 @@ static int DecodeImageData(VP8LDecoder* const dec, uint32_t* const data,
|
||||
} else { // Not reached
|
||||
goto Error;
|
||||
}
|
||||
assert(br->eos_ == VP8LIsEndOfStream(br));
|
||||
}
|
||||
|
||||
br->eos_ = VP8LIsEndOfStream(br);
|
||||
if (dec->incremental_ && br->eos_ && src < src_end) {
|
||||
RestoreState(dec);
|
||||
} else if (!br->eos_) {
|
||||
|
@ -155,9 +155,10 @@ static WEBP_INLINE int VP8LIsEndOfStream(const VP8LBitReader* const br) {
|
||||
|
||||
// For jumping over a number of bits in the bit stream when accessed with
|
||||
// VP8LPrefetchBits and VP8LFillBitWindow.
|
||||
// This function does *not* set br->eos_, since it's speed-critical.
|
||||
// Use with extreme care!
|
||||
static WEBP_INLINE void VP8LSetBitPos(VP8LBitReader* const br, int val) {
|
||||
br->bit_pos_ = val;
|
||||
br->eos_ = VP8LIsEndOfStream(br);
|
||||
}
|
||||
|
||||
// Advances the read buffer by 4 bytes to make room for reading next 32 bits.
|
||||
|
Loading…
Reference in New Issue
Block a user