1015659 - Use QR Code to video sync profiles

Status: RESOLVED FIXED

(Core :: Gecko Profiler, defect)

Description

[Benoit Girard (:BenWa)]

Right now we use a binary counter but it's very difficult to do ORC. Instead we should use a QR code approach.

Comment 1

[Benoit Girard (:BenWa)]

Attachment: WIP

Comment 2

[Benoit Girard (:BenWa)]

Attachment: Screenshot

Comment 3

[Benoit Girard (:BenWa)]

You said on IRC you think this could use the color bar. I'm assuming you mean the frame coloring? I picked QR code because they work with any orientation and they are easy to find a frame and can encode a reasonable amount of data and have redundancy/checksums.

I'd like to hear if we can achieve a workable solution without qr code because it is annoying to deal with a parsing library.

Comment 4

[Benoit Girard (:BenWa)]

CCing mchang since it might help with the using a high speed camera to measure frames.
CCing wlach since it might be interesting feature for eideticker to use.

Comment 5

[Benoit Girard (:BenWa)]

Attachment: qrcode_table.h

I forgot to attach this. Putting here to be merged into the patch. Just so I don't lose the patch.

Comment 6

[Benoit Girard (:BenWa)]

Taking needinfo off. I had a conversation with vlad in person.

Comment 7

[Benoit Girard (:BenWa)]

Attachment: Patch: Replace frame counter by a QRCode

Comment 8

[Benoit Girard (:BenWa)]

Attachment: Patch: Replace frame counter by a QRCode

Comment 9

[Jeff Muizelaar [:jrmuizel]]

Comment on attachment 8440332 [details] [diff] [review]
Patch: Replace frame counter by a QRCode

Review of attachment 8440332 [details] [diff] [review]:
-----------------------------------------------------------------

::: gfx/layers/composite/LayerManagerComposite.cpp
@@ +313,5 @@
>  
> +#ifdef MOZ_PROFILING
> +// Only build the QR feature when profiling to avoid bloating
> +// our data section.
> +#include "qrcode_table.h"

Maybe add a comment as to where this data came from and what it is.

@@ +355,2 @@
>  
> +    int padding = 2;

Maybe give a name to 21?

@@ +368,5 @@
> +                          effects,
> +                          opacity,
> +                          gfx::Matrix4x4());
> +
> +    // Change the color to black

Instead write: Draw a black square for every bit set in qr[index]

@@ +378,5 @@
> +        if (currBit == 0) {
> +          currBit = 128;
> +          i++;
> +        }
> +        if (qr[i] & currBit) {

Can you stop computing currBit incrementally and just do it directly from the loop variable. That will make it a little easier to understand what's going on here.

@@ +385,5 @@
> +                                          bitWidth, bitWidth),
> +                                clip,
> +                                effects,
> +                                opacity,
> +                                gfx::Matrix4x4());

This seems like a terrible way to draw this, but it probably doesn't matter.

Comment 10

[Benoit Girard (:BenWa)]

Attachment: Patch: Replace frame counter by a QRCode

https://tbpl.mozilla.org/?tree=Try&rev=f06b165fa29f

Comment 11

[Benoit Girard (:BenWa)]

Attachment: patch v3

https://hg.mozilla.org/integration/mozilla-inbound/rev/2b1d50423271

Comment 12

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/2b1d50423271