Starting to test Comskip with h.264 support

[Djc208]

Originally Posted by WhiteWhisker

out of curiosity what speed is to be expected on h.264 files currently? I am processing rather large 3 hour HD basketball games and its taking approx 6 hours to process each, seems to be about 11fps or so? I am running on an athlon 64 x2 4200+ at medium priority...is this about right?

I haven't timed h.264 files but that doesn't sound too far off. It is far slower than with MPEG files, but far better than nothing, which is all we had before.

[jelder]

JetreL.....Just wanted to point out that I will be starting up this task of running comskip on multiple machines soon. I have 2 Quad core PCs that will be available for operation in about a week. I have a backlog of about 400GB of ts files from my HDPVR that need processing.

I'll let everyone know how I did it when it's done.

-Brian



Did you ever get this to work? I cannot get my other computer to find the sage tv files on the mapped drive.

[gplasky]

I believe you'll need to use UNC naming, not mapped drives.

Gerry

[jelder]

Thanks for the response Gerry. I am trying to get it to work using DirMon 2 on a remote computer. I have tried mapped drives and UNC and neither seem to work. DirMon2 allows me to add the directory under the Job Management tab, but Comskip does not seem to find any of the files to start processing. Any other ideas?

[Chaos~Theory]

Hey Erik!

Just wanted to tell you that the new (Donator's version) of Comskip works beautifully!!! I only had one failure out of roughly 180 files! It is amazing how fast it goes through the SD files!!! 60min file (Standard DVD res) takes less than 6 minutes to process!!!! And the TS files are running at least as fast as 60min (Great res) takes, at most, 20-40mins to process!!! I love the 'skip b-frame' option, btw.... huge difference in speed!

I 'am' running on a AMD Phenom, quad core 2.1gHz processors, but the speed isn't just the processor's doing..... the new verson is just **FAST**!!!

(Sorry for all the "!!!!!!", I am very excited to *finally* have commercial scanning working on all my recording formats!!!)

What ever you did in the last update fixed all the problems I had been having!

All I need to do now is tweak the scan and it will be almost perfect!

I would reccomend for everyone to send Erik a donaton and pick up the 'early access' verson!!! It is WELL worth it!!!!!

Keep up the fantastic work!!!
-Chris

[Eckwell]

What is the skip b-frame option?

[Chaos~Theory]

Originally Posted by Eckwell

What is the skip b-frame option?

The 'b-frame' option, which is only available to donators of Comskip, skips the 'b-frames' of H.264 recordings, which are not necessary for commercial scanning, which *greatly* increases it's speed of processing those files. I'm sure Erik, can better describe the workings of how it works.....

Wikipedia's definition of a 'b-frame':

The other two types of frames are P-Frames ('Predicted pictures), and B-Frames (Bi-predictive pictures). P-frames and B-frames help to reduce the size of the video and therefore improve video compression rates. P-frames do this by allowing the video encoder to store only the changes made in respect to the previous I-Frame (full frame). For example, in a scene where a car moves across a stationary background, only the car's movements will be encoded. This allows the video encoder to save space, as it does not have to store the same stationary background found in previous frames in the P-frame. P-Frames are also known as delta-frames. B-frames help to save space by allowing the video encoder to store data with reference to both the previous and precedent frames, this means that the B-frame can refer to the frame in front of and behind it, to specify its content. This allows for even more space to be saved than in contrast to P-frames.

Hope this answer your question..... and tempt you into donating to Erik! Really, he does deserve thanks , or better, some compensation for all the time he has put into Comskip, and into h.264 scanning, of which, SA has seemed to basically given up on.

-Chris

[sundansx]

does anyone know if the skip_bframes option reduces the accuracy? Why is it not turned on by default? unstable?
thanks.

[erik]

From the readme.txt

- Setting skip_b_frames=2 will have Comskip skip frames on HD but not on SD, only available for donators

Its because skipping B frames reduces accuracy a couple of frames (I have had people complaining detection to be off by 2 frames) and skipping B frames will NOT work in regular SD USA broadcast because the black frame detection will fail.
Setting
skip_b_frames=2
is safer as it avoids skipping for SD recordins (where speed in general is not a problem)

[TallMomof2]

I'm running the latest donator version and I agree that it works quite well. HD mpg files (from my HDHR) process incredibly fast with good accuracy. ts files are a bit slower but still faster than live. Occasionally, commercials are missed (network will throw up a logo in between commercials) are the end of a show not detected (Comedy Central frequently doesn't put up a logo at the beginning of the last segment of The Daily Show because it's going into the credits) but those are minor. But all in all I get roughly 90% accuracy.

[Taddeusz]

Yea, I've been wondering how to go about tweaking accuracy. I recorded the new Scrubs this week through my HDHR and it didn't detect any ads whatsoever. Source was 720p MPEG2 with 5.1ch audio.

[erik]

Follow this
http://www.kaashoek.com/comskip/viewtopic.php?f=5&t=169
or this
http://www.kaashoek.com/comskip/viewtopic.php?f=5&t=34

[Taddeusz]

I started the tuning instructions and I think I figured out why it's not detecting ads on this particular station. There is a small KOCO-DT that they have in the upperish right corner of the screen that is displayed all the time, even during ads. The regular ABC logo on the bottom right of the screen is only displayed during the program. Comskip seems to be locking onto the KOCO-DT logo rather than the ABC logo and seems to be depending on that for ad detection. Since it never goes away according to it there are no ads.

[hemicuda]

You may have already found this in the notes, but there is a setting that will limit the logo scanning to a particular area of the frame.

[erik]

set
logo_at_bottom=1

[SWKerr]

Has anyone have a tweaked version of the ini for the HD-PVR that they are happy with and are willing to post.

I have found it is generally good right out of the box but I would like to see something from anyone who thinks they have made an improvement over standard.

The most annoying issue I seem to have is a short section between commercials that is marked as normal. Is there a setting that would set a minimum limit of time for a clear\non-add area? This seems like something that could be fixed.

[kevine]

Originally Posted by SWKerr

Has anyone have a tweaked version of the ini for the HD-PVR that they are happy with and are willing to post.

I have found it is generally good right out of the box but I would like to see something from anyone who thinks they have made an improvement over standard.

The most annoying issue I seem to have is a short section between commercials that is marked as normal. Is there a setting that would set a minimum limit of time for a clear\non-add area? This seems like something that could be fixed.

This is a tricky thing. The reason is different affiliates handle commercials differently. In order to get every second out of the commercial time, they squeeze things together (ie: very little gap). While others have plenty of space in between. Also, screen logos, fade in/fade out, etc. So an INI in one are area may not work well at all in another. However, I always thought it would be cool to add threads for each of the affiliates and/or areas to share these ini's with each other.

[Taddeusz]

Originally Posted by erik

set
logo_at_bottom=1

Cool, that seems to have cleared that up.

Now I need to tweak the settings to get 480i recordings from my HD-PVR to be detected better.

[ghostlobster]

Originally Posted by Chaos~Theory

Really, he does deserve thanks , or better, some compensation for all the time he has put into Comskip, and into h.264 scanning, of which, SA has seemed to basically given up on.

-Chris

Sorry, but I've got to call out that comment. Jere has certainly not given up on h.264 work. He just released another beta of SA Suite to the testers and it is working just fine.
I do agree whole heartedly that Erik's work here is outstanding and he deserves the applause and the compensation, without a doubt! However, it's unfair and inaccurate to say that Jere has packed it in.

OK, I'l step down from the
Now...back to our regularly scheduled postings....

[Eckwell]

Originally Posted by Chaos~Theory

Hope this answer your question..... and tempt you into donating to Erik! Really, he does deserve thanks , or better, some compensation for all the time he has put into Comskip, and into h.264 scanning, of which, SA has seemed to basically given up on.

-Chris

Thanks! Although I donated in early March 08!