Implement Biquad lowpass and highpass filters according to spec

Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html

Committed: https://crrev.com/10494397a89162ce998d4ab18761a530d690d67c
Cr-Commit-Position: refs/heads/master@{#399519}

[Raymond Toy, 2016-04-18 20:08:32]

Description was changed from

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly.  Update implementation to match spec.

See WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.

BUG=
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

to

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

[Raymond Toy, 2016-04-18 20:12:59]

rtoy@chromium.org changed reviewers:
+ hongchan@chromium.org

[Raymond Toy, 2016-04-18 20:12:59]

PTAL.

The main change is Biquad.cpp, with updated results for biquad-lowpass.html and
biquad-highpass.html.  In modifying these, individual thresholds were added for
each test, resulting in adding thresholds for the other tests as well.  The
iirfilter test and getFrequencyResponse test changed because the output changed.

[Raymond Toy, 2016-04-18 20:13:39]

On 2016/04/18 at 20:12:59, Raymond Toy wrote:
> PTAL.
> 
> The main change is Biquad.cpp, with updated results for biquad-lowpass.html
and biquad-highpass.html.  In modifying these, individual thresholds were added
for each test, resulting in adding thresholds for the other tests as well.  The
iirfilter test and getFrequencyResponse test changed because the output changed.

Should I also add an entry to chrome features?

[hongchan, 2016-04-20 16:27:47]

On 2016/04/18 20:13:39, Raymond Toy wrote:
> On 2016/04/18 at 20:12:59, Raymond Toy wrote:
> > PTAL.
> > 
> > The main change is Biquad.cpp, with updated results for biquad-lowpass.html
> and biquad-highpass.html.  In modifying these, individual thresholds were
added
> for each test, resulting in adding thresholds for the other tests as well. 
The
> iirfilter test and getFrequencyResponse test changed because the output
changed.
> 
> Should I also add an entry to chrome features?

We agreed on posting this change to chromestatus.com to notify developers. Also
there seems to be a compilation error.

[hongchan, 2016-04-20 17:50:23]

On 2016/04/20 16:27:47, hoch wrote:
> On 2016/04/18 20:13:39, Raymond Toy wrote:
> > On 2016/04/18 at 20:12:59, Raymond Toy wrote:
> > > PTAL.
> > > 
> > > The main change is Biquad.cpp, with updated results for
biquad-lowpass.html
> > and biquad-highpass.html.  In modifying these, individual thresholds were
> added
> > for each test, resulting in adding thresholds for the other tests as well. 
> The
> > iirfilter test and getFrequencyResponse test changed because the output
> changed.
> > 
> > Should I also add an entry to chrome features?
> 
> We agreed on posting this change to http://chromestatus.com to notify
developers. Also
> there seems to be a compilation error.

Oh, please disregard my last comment. The difference is quite negligible except
for some corner cases, so I am fine with landing this feature without the
developer notification.

[Raymond Toy, 2016-04-26 18:37:52]

PTAL.

[hongchan, 2016-04-26 18:41:41]

lgtm

[Raymond Toy, 2016-05-13 22:13:53]

I'm going to wait a little while before landing this pending more data on the Q
values used for the lowpass and highpass filters.

[Raymond Toy, 2016-05-17 21:23:58]

Description was changed from

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

to

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

[Raymond Toy, 2016-06-13 16:18:11]

The CQ bit was checked by rtoy@chromium.org

[Raymond Toy, 2016-06-13 16:18:12]

The patchset sent to the CQ was uploaded after l-g-t-m from
hongchan@chromium.org
Link to the patchset: https://codereview.chromium.org/1885723003/#ps80001
(title: "Rebase")

[commit-bot: I haz the power, 2016-06-13 16:18:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1885723003/80001

[commit-bot: I haz the power, 2016-06-13 17:28:20]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-06-13 17:28:21]

Try jobs failed on following builders:
  win8_chromium_ng on tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win8_chromium_ng/...)

[Raymond Toy, 2016-06-13 17:58:20]

The CQ bit was checked by rtoy@chromium.org

[commit-bot: I haz the power, 2016-06-13 17:59:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1885723003/80001

[commit-bot: I haz the power, 2016-06-13 20:12:08]

Description was changed from

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

to

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

[commit-bot: I haz the power, 2016-06-13 20:12:10]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2016-06-13 20:12:37]

CQ bit was unchecked

[commit-bot: I haz the power, 2016-06-13 20:13:21]

Description was changed from

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update 
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html
==========

to

==========
Implement Biquad lowpass and highpass filters according to spec

The WebAudio spec has changed the definition of the lowpass and
highpass filters slightly because some lowpass and highpass filters
could not be represented by the existing filters.  Update
implementation to match spec.

This will cause some very slight difference in sound quality for some
values of Q.  The new filters were careful to preserve the sound as
much as possible.

WebAudio issue https://github.com/WebAudio/web-audio-api/issues/771.
Resolution: https://github.com/WebAudio/web-audio-api/pull/795
Feature: https://www.chromestatus.com/features/5687523284090880

BUG=597432
TEST=biquad-*.html, iirfilter-getFrequencyResponse.thml, iirfilter.html

Committed: https://crrev.com/10494397a89162ce998d4ab18761a530d690d67c
Cr-Commit-Position: refs/heads/master@{#399519}
==========

[commit-bot: I haz the power, 2016-06-13 20:13:23]

Patchset 5 (id:??) landed as
https://crrev.com/10494397a89162ce998d4ab18761a530d690d67c
Cr-Commit-Position: refs/heads/master@{#399519}