Simply get rid of an intermediate buffer of size width x height, by
using the fact that stride == width in this case.
Change-Id: I92376a2561a3beb6e723e8bcf7340c7f348e02c2
no precision loss observed
speed is not really faster (0.5% at max), as forward-WHT isn't called often.
also: replaced a "int << 3" (undefined by C-spec) by a "int * 8"
( supersedes https://gerrit.chromium.org/gerrit/#/c/48739/ )
Change-Id: I2d980ec2f20f4ff6be5636105ff4f1c70ffde401
it's not often the case, but could happen, that chroma has non-zero
coeff but luma hasn't. In such case, we should skip luma right away
Change-Id: I9515573ffaec8aad8b069d2c02ffbda4a6eff97c
Removed a call to WebPParseHeaders() inside VP8GetHeaders(). This was not needed
anyway, as all call flows already call WebPParseHeaders() before calling
VP8GetHeaders().
This avoids duplicate calls to WebPParseHeaders().
Change-Id: Icb2d618bd26c44220d956c17a69c9c45a62d5237
The output surface CAN be changed inbetween calls to
WebPIUpdate() or WebPIAppend(), but with precautions.
Change-Id: I899afbd95738a6a8e0e7000f8daef3e74c99ddd8
This applies to images with optional chunks (e.g. images with ALPH
chunk,
ICCP chunk etc). Before this, the incremental decoding used to work like
non-incremental decoding for such files, that is, no rows were decoded
until
all data was available.
The change is in 2 parts:
- During optional chunk parsing, don't wait for the full VP8/VP8L chunk.
- Remap 'alpha_data' pointer whenever a new buffer is allocated/used in
WebPIAppend() and WebPIUpdate().
Change-Id: I6cfd6ca1f334b9c6610fcbf662cd85fa494f2a91
new option: -blend_alpha 0xrrggbb
also: don't force picture.use_argb value for lossless. Instead,
delay the YUVA<->ARGB conversion till WebPEncode() is called.
This make the blending more accurate when source is ARGB
and lossy compression is used (YUVA).
This has an effect on cropping/rescaling. E.g. for PNG, these
are now done in ARGB colorspace instead of YUV when lossy compression
is used.
Change-Id: I18571f1b1179881737a8dbd23ad0aa8cddae3c6b
user can now call WebPEncode() with any YUVA or ARGB format, for
lossy or lossless compression
also: simplified error reporting, which is done in WebPPictureARGBToYUVA()
and WebPPictureYUVAToARGB()
Change-Id: Ifb68909217175bcf5a050e5c68d06de9849468f7
(cherry picked from commit 07d87bda1b)
transfer ownership of chunk passed in ChunkSetNth(). prevents freeing
the chunk in e.g., MuxImageParse() when a partial assignment (alpha but
no image) has occurred.
Change-Id: Ia69656b04fdf50f098f3816b54abd4e191248de3
Saturation was done on input coeff, not quantized one.
This saturation is not absolutely needed: output of FTransformWHT
is in range [-16320, 16321]. At quality 100, max quantization steps is 8,
so the maximal range used by QuantizeBlock() is [-2040, 2040].
But there's some extra bias (mtx->bias_[] and mtx->sharpen_[]) so
it's better to leave this saturation check for now.
addresses issue #145
Change-Id: I4b14f71cdc80c46f9eaadb2a4e8e03d396879d28
* merge cost calculation functions (BitsEntropy() and HuffmanCost())
* have HistogramAdd() specialized into separate functions
* use threshold to bail-out early
* revamp code a bit
* also: save memory by freeing free(histogram_image)
Change-Id: I8ee5d2cfa1462d5d6ea6361f5c89925a3720ef55
* VP8L shouldn't have an alpha chunk
* expect an animation to only contain frames, not a mix of image chunks
* enforce ANIM/ANMF order
* expect a full frame in a complete file
Change-Id: I953a8b6058f9bc00f1d042635548f158abdf6fce
