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Discussion Starter · #1 ·
Hi


Even though I'm fairly experienced with computerstuff, I'm new to media players. I have been reading a lot about these, but much i written in expectation that the reader has full knowledge of everything :)


Firstly:

- Could someone please explain short and precise, what is this thing "Reframing" that a mediaplayer should be able to handle?



Initially I was set to buy the WDTV. But I can read "it has problems with 24p playback / 23.976". I can't find a precise description of what the problem is, though?? Also it should have synchronization problems when showing subtitles, and I'm in Denmark, Europe, so subtitles are important.


Important to me are:

True 24p e.g. 23.976 handling

DTS HD MA throughput

Subtitles handles correctly

Playing all various 1080p files and containers


- So, secondly, which mediaplayers should be on my shortlist?



WDTV seems deemed by the subtitles and "24p problem" (that I don't know what is)

Xtreamer doesn't have 24p support. I don't care for promises in future firmware-release as the may, or may not, come. I prefer the working thing.


Does the PCH A110 meet the above requriements without problems? And does it have a current chipset so I don't start out with "old technology"


And how do the EGreat EG-M34A compare.


And which ones more to be on the list...


Thanx in advance

Jens
 

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Quote:
Originally Posted by JENC /forum/post/16979718


Could someone please explain short and precise, what is this thing "Reframing" that a mediaplayer should be able to handle?

In video compression the current video frame may consist of pixels taken from previous "reference" frames. This is done to reduce the file's size but has no impact on video quality at all. So for example, if MediaInfo indicates 5 ref frames, then there will be times when the media player will have to store 5 previous frames in memory in order to take pixels from them to build the current video frame. The ref frame number listed by MediaInfo is just the maximum number of frames that a player "might" have to store in memory. Most of the time during movie playback the number of ref frames is below the maximum, with ref frame spikes occurring during action scenes. However, if the media player doesn't have enough memory to store the necessary ref frames, then video studdering or audio dropout will occur. Some media players handle this out-of-memory condition better than others.
 

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About reference frames:

http://wdtv.wetpaint.com/page/H.264+...e+frames+specs

Thanks to Shizzzon for his great work on that!

Reframes for most sigma 8635 chip players (e.g. WD HD TV, Egreat M34A, Pocornhour A-110) are about the same as that of WD HD TV with firmware 1.01.01 or above.


About 24p:


Most modern 1080p TV's have a 1080/24p mode (called true cinema or otherwise, depends on the brand). To use that mode (instead of the regular 1080/50 or 1080/60):

1. The player must be able to output 24p (or 24fps, 24Hz it's the same)

2. If the file is not exactly 24fps (and most movies are 23,976 fps) the player must able to "manipulate" the file ("change" the fps to 24 and synchronize the audio with the new refresh rate). Right now only the NMTs do that properly. Another feature they have is "framerate sync" which recognizes which movie is 23,976 and the player conveniently autoswitches output to 1080/24p so you don't have to manually do it yourself.


Egreat M34A is probably the cheapest NMT right now that fulfills your requirements (though no player plays "all files" to be honest, I'd say "most files"), shares the same firmware and specs with A-110 (only the logos are different, same Syabas middleware) and the only differences are:

1. On the A-110 you can fit a SATA (sata connection) hard drive internally, on the Egreat externally (same sata connection) and

2. The A-110 has a USB port that connects to your pc for access to it's SATA internal SATA drive, which the M34A lacks for it's external drive...
 

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Quote:
Originally Posted by sinker442 /forum/post/16980821


If the file is not exactly 24fps (and most movies are 23,976 fps) the player must able to "manipulate" the file ("change" the fps to 24 and synchronize the audio with the new refresh rate).

that can't be correct. as you are implying a bluray player will decode a DTS-HD stream (as an example), resample it to 1.001/1.000 and then re-encode it on the fly to DTS-HD again. i would imagine this does not happen.


what a proper player does is realise the difference between 23.976fps and 24fps.


it will then output to the tv @ either 23.976Hz or 24Hz. Only NMTs can do this, WDTV can't. Each frame is shown for one refresh, because of the mismatch between 23.976 and 24fps the wdtv suffers from a 'micro-stutter' every 40 seconds.


although in some scenes theres nothing 'micro' about it.
 

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I believe that 24Hz is just a simple and non-confusing way of naming the actual 23.976 framerate - in practice, exact 24Hz is never used except in cinema projectors...I believe a 24Hz TV can sync to both 24Hz and 23.976Hz, and all sources are actually 23.976Hz and that's what BD players usually output...I wander why a HTPC (or a media player) would be made to only run at 24Hz exactly - no TV expects 24Hz, most primarily assume it's 23.976...it however doesn't hurt to leave the exact 24Hz output for those encodes that are truly 24fps (by mistake or by design
)...
 

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Quote:
Originally Posted by sinker442 /forum/post/16981779


Not reencoding, just correct sync of audio and video.

On an HTPC to get 24p to play correctly you use Reclock for the same reason...

No, you are wrong.


To do what you say either there will be a jump in video (every 41.6seconds) or alot of dropped packets in the audio (VERY noticeable). Neither happens on a standalone bluray player.


PC's are not standalone, and reclock is not needed if display refresh matches fps. Standalones do not do the same thing, except xbmc on xbox. Reclock takes a decoded stream and stretches/squashes the audio to match the changed framerate. Standalone players bitstream the audio, ergo, no reclock type stuff.

Quote:
Originally Posted by mytbyte /forum/post/16982101


I believe that 24Hz is just a simple and non-confusing way of naming the actual 23.976 framerate - in practice, exact 24Hz is never used except in cinema projectors...I believe a 24Hz TV can sync to both 24Hz and 23.976Hz, and all sources are actually 23.976Hz and that's what BD players usually output...I wander why a HTPC (or a media player) would be made to only run at 24Hz exactly - no TV expects 24Hz, most primarily assume it's 23.976...it however doesn't hurt to leave the exact 24Hz output for those encodes that are truly 24fps (by mistake or by design
)...

i know that Taken, and The Warlords are definitely 24.000fps.


i think you are right re tv's accepting 23.976 AND 24.000Hz.


nvidia graphics cards definitely have discrete seperate options (23.98Hz and 24.00Hz.
 

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Quote:
Originally Posted by lmaolmao /forum/post/16982502


i know that Taken, and The Warlords are definitely 24.000fps. i think you are right re tv's accepting 23.976 AND 24.000Hz.

Plenty of 24.00fps Blu-rays released here in the Nordic countries. Yes, televisions accept both 23.976 and 24.00.
 

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Actually it's not a problem to accept 24 or 23.976 (most flat TVs are multisync devices and can sync to almost any combination of scan/refresh within a range) but rather being able to run them in their exact multiples (72Hz for example)...older Panasonics are known to accept 24Hz, but convert them to 60Hz at display (they will not report "unsupported resolution")...Philips's latest sets, on the other hand, boast 24Hz compatibility but they do the same thing today that panny did years ago, converting 24Hz to 60Hz...


A major OT, apologies for that
 

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Quote:
Originally Posted by lmaolmao /forum/post/16982502


No, you are wrong.


To do what you say either there will be a jump in video (every 41.6seconds) or alot of dropped packets in the audio (VERY noticeable). Neither happens on a standalone bluray player.

PC's are not standalone, and reclock is not needed if display refresh matches fps. Standalones do not do the same thing, except xbmc on xbox. Reclock takes a decoded stream and stretches/squashes the audio to match the changed framerate. Standalone players bitstream the audio, ergo, no reclock type stuff.




i know that Taken, and The Warlords are definitely 24.000fps.


i think you are right re tv's accepting 23.976 AND 24.000Hz.


nvidia graphics cards definitely have discrete seperate options (23.98Hz and 24.00Hz.

You are saying the same thing as me...

I'm not talking about movies that are exactly 24fps. These play fine on any pc and all media players like WD that output 24p. The problem is that most movies are NOT exactly 24fps, but 23,976fps and for those on a pc you need reclock, and on a media player you need the same proper manipulation of audio/video...
 

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no, i'm not.


i'm saying that pcs CAN output 23.976Hz, and so do proper mediaplayers and standalone bluray players. They dont need to speed up from 23.976 to 24.000fps because they are displaying at exactly 23.976Hz (recurring).


By running at 23.976Hz instead of 24.000Hz, there is no manipulation of audio and video.
 

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Discussion Starter · #12 ·
Thanx, sinker442 and others for fine and competent answers.


It turns out, I actually knew about the reframe principles, but wasn't aware of the english naming for this.


As for mediaplayer, the EGreat EG-M34A sounds to be a very fine pick for me. I'll read on about this one.


Thanx...!
 
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