Commit Graph

9 Commits

Author SHA1 Message Date
Yaowu Xu
8c31484ea1 fix more merge issues
With this fix, the experimental branch now builds and encodes correctly
with the following two configure options respectively:
--enable-experimental --enable-t8x8
--enable-experimental

Change-Id: I3147c33c503fe713a85fd371e4f1a974805778bf
2011-07-21 09:01:53 -07:00
Deb Mukherjee
08f6471890 Add 8x8 transform to experimental branch
Please refer to previous commit messages for detailed info:
https://on2-git.corp.google.com/g/#change,5940
https://on2-git.corp.google.com/g/#change,6045

Change-Id: I8b16992f2f69c5a808ad40a3e32ef589cce7c59d
2011-07-20 09:49:22 -07:00
Yaowu Xu
5b42ae09ae experiment extending the quantizer range
Prior to this change, VP8 min quantizer is 4, which caps the
highest quality around 51DB. This experimental change extends
the min quantizer to 1, removes the cap and allows the highest
quality to be around ~73DB, consistent with the fdct/idct round trip
error. To test this change, at configure time use options:

--enable-experimental --enable-extend_qrange

The following is a brief log of changes in each of the patch sets

patch set 1:
In this commit, the quantization/dequantization constants are kept
unchanged, instead scaling factor 4 is rolled into fdct/idct.
Fixed Q0 encoding tests on mobile:
  Before:    9560.567kbps Overall PSNR:50.255DB VPXSSIM:98.288
  Now:   18035.774kbps Overall PSNR:73.022DB VPXSSIM:99.991

patch set 2:
regenerated dc/ac quantizer lookup tables based on the scaling
factor rolled in the fdct/idct. Also slightly extended the range
towards the high quantizer end.

patch set 3:
slightly tweaked the quantizer tables and generated bits_per_mb
table based on Paul's suggestions.

patch set 4:
fix a typo in idct, re-calculated tables relating active max Q
to active min Q

patch set 5:
added rdmult lookup table based on Q

patch set 6:
fix rdmult scale: dct coefficient has scaled up by 4

patch set 7:
make transform coefficients to be within 16bits

patch set 8:
normalize 2nd order quantizers

patch set 9:
fix mis-spellings

patch set 10:
change the configure script and macros to allow experimental code
to be enabled at configure time with --enable-extend_qrange

patch set 11:
rebase for merge

Change-Id: Ib50641ddd44aba2a52ed890222c309faa31cc59c
2011-01-19 13:22:35 -08:00
John Koleszar
c2140b8af1 Use WebM in copyright notice for consistency
Changes 'The VP8 project' to 'The WebM project', for consistency
with other webmproject.org repositories.

Fixes issue #97.

Change-Id: I37c13ed5fbdb9d334ceef71c6350e9febed9bbba
2010-09-09 10:01:21 -04:00
Yaowu Xu
b62d093efa Improve the accuracy of forward walsh-hadamard transform
Besides the slight improvement in round trip error. This
also fixes a sign bias in the forward transform, so the
round trip errors are evenly distributed between +1s and
-1s. The old bias seemed to work well with the dc sign bias
in old fdct,  which no longer exist in the improved fdct.

Change-Id: I8635e7be16c69e69a8669eca5438550d23089cef
2010-06-28 22:10:48 -07:00
Yaowu Xu
d0dd01b8ce Redo the forward 4x4 dct
The new fdct lowers the round trip sum squared error for a
4x4 block ~0.12. or ~0.008/pixel. For reference, the old
matrix multiply version has average round trip error 1.46
for a 4x4 block.

Thanks to "derf" for his suggestions and references.

Change-Id: I5559d1e81d333b319404ab16b336b739f87afc79
2010-06-24 13:17:58 -07:00
John Koleszar
94c52e4da8 cosmetics: trim trailing whitespace
When the license headers were updated, they accidentally contained
trailing whitespace, so unfortunately we have to touch all the files
again.

Change-Id: I236c05fade06589e417179c0444cb39b09e4200d
2010-06-18 13:06:11 -04:00
John Koleszar
09202d8071 LICENSE: update with latest text
Change-Id: Ieebea089095d9073b3a94932791099f614ce120c
2010-06-04 16:19:40 -04:00
John Koleszar
0ea50ce9cb Initial WebM release 2010-05-18 11:58:33 -04:00