Another 3 months development needed?

burnfox · 06-18-2008

All right,yestoday we know that M8 specs still pending,today we know
maybe,we have to wait 3 months more for the B-frame
link

The link above is a voting J.W started it to asking users on the official forum.

Can you accept that M8 can't playback B-frame video signals?

A、I accept it,waiting is torment,I hope that M8 could on the market,ASAP.

B、I do not! even it means I will suffer another 3-month delay,I prefer a perfect M8.

You guys could see the results in that link.

tails2 · 06-18-2008

Ha Ha HA, once again we get another delay, but this time he is trying to throw it as our choice. If we say we want to be able to playback B-frame video signals then they will delay it by 3 months but will say it is not their fault as it was the customer who chose it.

The little fate I had that this will come out with specs anywhere near what was originally said, is getting smaller and smaller everytime he opens his mouth.

sigh

darkado · 06-18-2008

who cares, release it already and update sw on the go

SteveMB93 · 06-18-2008

What's the B frame?

Th3_uN1Qu3 · 06-18-2008

Quote:

Originally Posted by SteveMB93

What's the B frame?

It's the reason you have to convert your videos for use with the M6.

tails2 · 06-18-2008

Quote:

Originally Posted by darkado

who cares, release it already and update sw on the go

Good idea darkado, let's hope they make a good decision about this. And let's hope even more that firmware updates will be much simpler than on the M6. Their firmware updates need to be more user friendly as not everyone wh might buy this will be tech savvy like us.

Quote:

Originally Posted by SteveMB93

What's the B frame?

Also a good question SteveMB93, so i check google and this came up:

Quote:

Originally Posted by webopedia

Short for bi-directional frame, or bi-directional predictive frame, a video compression method used by the MPEG standard. In a motion sequence, individual frames of pictures are grouped together (called a group of pictures, or GOP) and played back so that the viewer registers the video’s spatial motion. As the name suggests, B-frames rely on the frames preceding and following them. B-frames contain only the data that have changed from the preceding frame or are different from the data in the very next frame.

P-frames and B-frames are also referred to as delta frames.

Quote:

Originally Posted by Wikipedia

Bi-directional predicted frames (or slices)

Require the prior decoding of some other picture(s) in order to be decoded.
May contain both image data and motion vector displacements and combinations of the two.
Include some prediction modes that form a prediction of a motion region (e.g., a macroblock or a smaller area) by averaging the predictions obtained using two different previously-decoded reference regions.
In older standard designs (such as MPEG-2), B pictures are never used as references for the prediction of other pictures. As a result, a lower quality encoding (resulting in the use of fewer bits than would otherwise be the case) can be used for such B pictures because the loss of detail will not harm the prediction quality for subsequent pictures.
In H.264, may or may not be used as references for the decoding of other pictures (at the discretion of the encoder).
In older standard designs (such as MPEG-2), use exactly two previously-decoded pictures as references during decoding, and require one of those pictures to precede the B picture in display order and the other one to follow it.
In H.264, can use one, two, or more than two previously-decoded pictures as references during decoding, and can have any arbitrary display-order relationship relative to the picture(s) used for its prediction.
Typically require fewer bits for encoding than either I or P pictures do.

tails2 · 06-18-2008

Quote:

Originally Posted by Th3_uN1Qu3

It's the reason you have to convert your videos for use with the M6.

Does this mean that playback will not be possible if it is not included?

From reading on the web, it says it is required for use in showing the difference between frames in a movie.

Traps · 06-18-2008

There is some misinformation here.. I was following the huge amount of new posts by J.Wong, and it seems that this is in fact an hardware issue.

The problem is that the 6410 processor cannot do hardware decoding of B-frames. This is a problem because most video content found on the internet uses B-frames to improve compression ratio. One member asked if B-frames can be decoded using software-based codecs, but JW says that software decoding at full 720x480 will not be smooth. So basically there are two alternatives on that poll:

(1)
Don't change anything in hardware, and forget about hardware decoded B-frames. Software decoding is still possible but is unlikely to look good at full 720x480.

(2)
Use another processor, which would mean a 3 month delay. The Tegra APX2500 was mentioned, and it seems that Meizu has already contacted NVIDIA regarding the detailed specs (and decoding of B-frames in particular),

Personally, I'm shocked that Meizu has taken so long to realize that the 6410 can't do B-frames. They should be close to releasing a product, this is not the time to realize and react to this sort of problems!
Anyway, the answer seems clear to me: the 6410 is still one of the most advanced ARM CPUs in the market (there are still no smart-phones out there with processors this powerful)... so they should just forget about hardware decoding limitations and hurry the M8 out! It's not feasible to keep delaying it indefinitely, since you can't create a perfect machine!

PS: I read the threads where JW made his posts, but I used google-translation so there's a chance that I didn't understand everything clearly. Please correct me if I said anything that isn't true.

EDIT: I hope the fans choose (1), because (2) is a road to perdition IMO..

DusL · 06-18-2008

Google can help sometimes, although this has been a difficult one!

<frustratingly difficult information>

B-frames is the short hand for "bi-directional interpolated prediction frames". What that technically means is something even beyond my comprehention (great that Wong asks such a question that probably nobody understands), but I can get close I think.

It's a way of encoding video in which the keyframes contain not only information about the previous frame but also of the next frame. This is supposed to achieve more efficiënt encoding, using less bits to store the same information. Also it results in better quality(?) Negative aspects are that it requires twice the RAM to perform because of cashing and that it uses potentially higher CPU-usage.

From a more practical point of view, h.264 is a format which seems to support and (more importantly) push the usage of these b-frames. The AVI format seems to lack any rule that makes B-frames illegal, so encoders can use it. I have no idea about the other various formats, but it is likely that it will be a mix of b-frames and non-b-frames.

</frustratingly difficult information>

To say it easy, you won't be able to playback some video without b-frame support. You will need to reëncode the videos on your computer that has it in order to play them on your m8. How important this is depends on the unknown distribution of b-frame-video.

EDIT: read the post above this one, they supplement eachother pretty nicely

tails2 · 06-18-2008

So does this mean that one of the main PLUS points people were trying to make in favour of the M8, not having to encode/re encode file for playback, will be lost if they don't change the hardware?