Hauppauge HD-PVR & Colossus Support (2 Viewers)

[Klairic]

I'm still having the same problems as everyone else with losing a feed when broadcast format changes. Is this only on an audio change, or will a video change break things as well?

The current idea you guys are talking about is to add a delay after changing channels to make sure Media Portal is getting the right format. Is there any merit to looking at handling a hostile change in the middle of a feed? I'm wondering if any stations change their broadcast from one resolution to another, or change audio formats. If that happens, it seems like it would be better to detect a change in what's coming in, and then get the new a/v formats. That should take care of any possible problem. Not sure how much work that would be though, maybe I should take a look first.

 

[mm1352000]

Hi Klairic

Looks pretty good to me!
I'll try to ensure this gets into 1.2.0rc...

Thanks for contributing.

 

[mm1352000]

I'm still having the same problems as everyone else with losing a feed when broadcast format changes. Is this only on an audio change, or will a video change break things as well?

The current idea you guys are talking about is to add a delay after changing channels to make sure Media Portal is getting the right format. Is there any merit to looking at handling a hostile change in the middle of a feed? I'm wondering if any stations change their broadcast from one resolution to another, or change audio formats. If that happens, it seems like it would be better to detect a change in what's coming in, and then get the new a/v formats. That should take care of any possible problem. Not sure how much work that would be though, maybe I should take a look first.

The issue is with *encoding* changes in general. My understanding is that format changes (eg. 5.1 <--> 2 channel audio) sometimes happen in the broadcast world, and I think MP could handle that as long as your codecs can handle it (ie. the codecs would be the critical factor). Encoding changes are a completely different kettle of fish because MP would have to reconfigure the client side graph... like you said: support "hostile" changes.

Technically speaking, the issue with doing that is that I don't think it would be sufficient for the Colossus. From what I saw in Wile E's server logs, the Colossus sometimes changes the audio encoding flags on the audio ES in the PMT *even though Wile E didn't change input or channel*. We don't want glitches because of random PMT changes - we only want to pay attention to the meaningful ones. I'm not yet sure what bearing the PMT chosen on the server side has on the client side, which is why I wanted to look through Wile E's TsReader logs. If this issue has to be handled in TsReader (or somewhere on the client side) then the any fix is almost certain to have to wait for 1.3.0 - there would just be too much risk in those kinds of changes...

 

[WileECoyote]

I'm still having the same problems as everyone else with losing a feed when broadcast format changes. Is this only on an audio change, or will a video change break things as well?

The current idea you guys are talking about is to add a delay after changing channels to make sure Media Portal is getting the right format. Is there any merit to looking at handling a hostile change in the middle of a feed? I'm wondering if any stations change their broadcast from one resolution to another, or change audio formats. If that happens, it seems like it would be better to detect a change in what's coming in, and then get the new a/v formats. That should take care of any possible problem. Not sure how much work that would be though, maybe I should take a look first.

Hey Kliric,
The video will never change in the feed. Most of us have the STB set to HD 720p or 1080i and the Colossus encodes the feed to H264. This has never been an issue with the former HD-PVR and so far has not been an issue with the Colossus.

As far as the audio goes, I will let mm speak to that

Wile E.

 

[mm1352000]

Hey Kliric,
The video will never change in the feed. Most of us have the STB set to HD 720p or 1080i and the Colossus encodes the feed to H264. This has never been an issue with the former HD-PVR and so far has not been an issue with the Colossus.

As far as the audio goes, I will let mm speak to that

Wile E.

Hi Wile E

I don't mean to contradict you, but I'm curious: what happens if you have an MPEG 2 stream that comes through HDMI - does the Colossus re-encode it to h.264 on the fly? If it doesn't then anyone that can get MPEG 2 streams via HDMI and h.264 streams via any other analog input will have video encoding problems too.

mm

 

[elconejito]

Hey Kliric,
The video will never change in the feed. Most of us have the STB set to HD 720p or 1080i and the Colossus encodes the feed to H264. This has never been an issue with the former HD-PVR and so far has not been an issue with the Colossus.

As far as the audio goes, I will let mm speak to that

Wile E.

Hi Wile E

I don't mean to contradict you, but I'm curious: what happens if you have an MPEG 2 stream that comes through HDMI - does the Colossus re-encode it to h.264 on the fly? If it doesn't then anyone that can get MPEG 2 streams via HDMI and h.264 streams via any other analog input will have video encoding problems too.

mm

is that the same or different when you switch from one tuner to another? my Avermedia cards encode to MPG, then switch to colossus just fine. both recording and just watching tv

 

[sjeffrey]

Hey Kliric,
The video will never change in the feed. Most of us have the STB set to HD 720p or 1080i and the Colossus encodes the feed to H264. This has never been an issue with the former HD-PVR and so far has not been an issue with the Colossus.

As far as the audio goes, I will let mm speak to that

Wile E.

Hi Wile E

I don't mean to contradict you, but I'm curious: what happens if you have an MPEG 2 stream that comes through HDMI - does the Colossus re-encode it to h.264 on the fly? If it doesn't then anyone that can get MPEG 2 streams via HDMI and h.264 streams via any other analog input will have video encoding problems too.

mm

Wow, I left for a weekend and 3 new pages to read.
Does HDMI actually do MPEG2? I know this isn't an issue with component cables since it's in analog format but HDMI I'm not familiar enough with. I would assume that it's Colossus' job to decode the MPEG2 and then it will still encode as MPEG4, I don't suspect that will ever change. So for TVServer and MP Client, it's always MPEG4.

You guys have been talking about a longer pause for channel change and pmt versions for a bit. My take on it is that broadcast changes will still cause issues so a longer pause won't fix it. I still haven't tested Colossus with AC3 but with HD-PVR you can tell it's the hardware that has a "hickup" and not MP (the bling led flickers for a few seconds then back to solid). A recorded show in AC3 has no issues with commercials switching to 2 channel and then back to 5.1 so we already know MP can handle the switching from 5.1 to 2. Live TV on the other hand is different. It seems like HD-PVR stops sending data to handle the change and then starts sending packets again. Since you are playing back the live stream it's like you just hit a wall and can't go any further as there is no data to read. This is experienced as stutter in the client. Our "workaround" has always been to pause for 2-3 seconds and you would be fine for a while. This makes sure you won't hit the end of the stream again while HD-PVR switches format. Video, like WileE said, is a non issue probably since so far all STBs are fixed format. And more about the pause, I think we have all tried over the years to add, remove, make longer the pause after a channel change but we never got 100% success. BTW, I know SageTV has a configurable pause for the HD-PVR but I never tested Sage much to know if it's actually better for handling the PVR.

Well that's my input on the issue. Hopefully I'll have some free time soon. I've been spending all my non-working time on home renos...

 

[mm1352000]

I've *got* to go to bed - almost 2am and I've had too many late nights in a row. Brief answers/comments...

is that the same or different when you switch from one tuner to another? my Avermedia cards encode to MPG, then switch to colossus just fine. both recording and just watching tv

It is different.

Wow, I left for a weekend and 3 new pages to read.

Does HDMI actually do MPEG2? I know this isn't an issue with component cables since it's in analog format but HDMI I'm not familiar enough with. I would assume that it's Colossus' job to decode the MPEG2 and then it will still encode as MPEG4, I don't suspect that will ever change. So for TVServer and MP Client, it's always MPEG4.

I would have guessed differently since HDMI is a serial digital input on the Colossus input crossbar...

You guys have been talking about a longer pause for channel change and pmt versions for a bit. My take on it is that broadcast changes will still cause issues so a longer pause won't fix it. I still haven't tested Colossus with AC3 but with HD-PVR you can tell it's the hardware that has a "hickup" and not MP (the bling led flickers for a few seconds then back to solid). A recorded show in AC3 has no issues with commercials switching to 2 channel and then back to 5.1 so we already know MP can handle the switching from 5.1 to 2. Live TV on the other hand is different. It seems like HD-PVR stops sending data to handle the change and then starts sending packets again. Since you are playing back the live stream it's like you just hit a wall and can't go any further as there is no data to read. This is experienced as stutter in the client. Our "workaround" has always been to pause for 2-3 seconds and you would be fine for a while. This makes sure you won't hit the end of the stream again while HD-PVR switches format.

That would be certainly be true as long as the Colossus/HDPVR are doing the encoding. When it is a digital input (ie. SPDIF) then it is a different story...

Video, like WileE said, is a non issue probably since so far all STBs are fixed format.

Not sure about that one yet. When it is an analog input on the Colossus/HDPVR then sure - the video is always encoded to h.264 so no worries. The trouble might arrive when you're switching between analog and HDMI inputs (assuming the HDMI input is not re-encoded).

And more about the pause, I think we have all tried over the years to add, remove, make longer the pause after a channel change but we never got 100% success. BTW, I know SageTV has a configurable pause for the HD-PVR but I never tested Sage much to know if it's actually better for handling the PVR.

Interesting. Ultimately I think the best solution might be to handle the so-called "hostile" encoding changes as mentioned by Klairic, but like I said earlier, there seem to be issues with Hauppauge's drivers at the moment. At least that is my take on it anyway...

Okay, I'm off to bed. Still yet to get a chance to look through Wile E's client logs. I hope to do that tomorrow. Talk to you all again soon...

 

[WileECoyote]

Wow, I left for a weekend and 3 new pages to read.
Does HDMI actually do MPEG2? I know this isn't an issue with component cables since it's in analog format but HDMI I'm not familiar enough with. I would assume that it's Colossus' job to decode the MPEG2 and then it will still encode as MPEG4, I don't suspect that will ever change. So for TVServer and MP Client, it's always MPEG4.

Hey SJeffrey,
I'm with you on this one. I dont know enough about HDMI to make a determination. I was speaking mainly for the Component Inputs. It should consistently put out H264 video...

You guys have been talking about a longer pause for channel change and pmt versions for a bit. My take on it is that broadcast changes will still cause issues so a longer pause won't fix it. I still haven't tested Colossus with AC3 but with HD-PVR you can tell it's the hardware that has a "hickup" and not MP (the bling led flickers for a few seconds then back to solid). A recorded show in AC3 has no issues with commercials switching to 2 channel and then back to 5.1 so we already know MP can handle the switching from 5.1 to 2. Live TV on the other hand is different. It seems like HD-PVR stops sending data to handle the change and then starts sending packets again. Since you are playing back the live stream it's like you just hit a wall and can't go any further as there is no data to read. This is experienced as stutter in the client. Our "workaround" has always been to pause for 2-3 seconds and you would be fine for a while. This makes sure you won't hit the end of the stream again while HD-PVR switches format. Video, like WileE said, is a non issue probably since so far all STBs are fixed format. And more about the pause, I think we have all tried over the years to add, remove, make longer the pause after a channel change but we never got 100% success. BTW, I know SageTV has a configurable pause for the HD-PVR but I never tested Sage much to know if it's actually better for handling the PVR.

I think we might be comparing oranges to apples on a few points?

- The HD-PVR stutter - This may have been resloved recently by mm's refactoring of the classes, so we dont know that the issues still applies? Have you tried the HD-PVR with the newest library mm posted?

- The HD-PVR Recordings - The reason I dont think this was an issue is because the HD-PVR encoded 2 channel sources to AC3, whereas the Colossus encodes 2 channel sources to AAC. MediaPortal would not have to switch codecs with the HD-PVR because both sources 5.1 & 2 channel were both encoded to AC3, whereas the Colossus does have to switch codecs because 5.1 is encoded AC3 and the 2 channel is encoded AAC. (Im starting to believe this is a downfall with the Colossus. I would be nice if they would give us the option like they did with the HD-PVR.)

- The HD-PVR Live TV - I agree on this, I think it was a hardware issue with the HD-PVR. But maybe someone with an HD-PVR can test to see if it is still an issue?

 

[WileECoyote]

Hey Kliric,
The video will never change in the feed. Most of us have the STB set to HD 720p or 1080i and the Colossus encodes the feed to H264. This has never been an issue with the former HD-PVR and so far has not been an issue with the Colossus.

As far as the audio goes, I will let mm speak to that

Wile E.

Hi Wile E

I don't mean to contradict you, but I'm curious: what happens if you have an MPEG 2 stream that comes through HDMI - does the Colossus re-encode it to h.264 on the fly? If it doesn't then anyone that can get MPEG 2 streams via HDMI and h.264 streams via any other analog input will have video encoding problems too.

mm

Hey mm,
Nope, no contradiction, I was speaking directly to the Component inputs. Forgot that Kliric was using HDMI.

I cannot speak to what will happen with the HDMI because it is a digital input, but my thought is the TS encoder will take any input and encode to H264? Since we are not flipping encoders (MP is hard coded to ONLY use the TS encoder) then it shouldnt be an issue?

Just my 2 cents (convert that to whatever currency you are using )

NOTE: mm, the DD issue has been around for a long time so don't feel like it needs to be resolved tonight, the Colossus works great with DD turned off. We just appreciate your attention and assistance that got us this far! We will get there, it may take a little time