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Discussion Starter · #1 ·
I bought a T301, mostly to be used as a video player for my daughter to replace her Sansa Fuze.

Because it has an 800x600 display, it should be able to display an unadulterated, full 720x480 DVD video, but due to to space issues, I figured I'll reduce them to 400x300 (1/2 resolution) to save place while still have a reasonable good picture quality. However, I noticed that regardless off the resolution used, the video do not use the full display (at least with the Gallery app), so I'd like to know what is the actual resolution used, so I can create my video files accordingly.

Also, is there a video player that either uses the full 800x600 display, or can display videos without automatic stretching to some predetermined area like Gallery?

The attached picture shows a 400x300 video as displayed on the T301 using the Gallery app.

TIA
 

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Discussion Starter · #2 ·
Hmmm, I guess I may be the only one trying to use the T301 as a 7" portable video player?

In any case, I experimented quite a bit with a couple of encoders, but mainly Handbrake, and the T301 can display a great quality, 720x480 mp4 video compressed with the H.264 codec that fills up almost all the display. However, there's a catch: for some reason, at some point it stops playing, and tells that it can't play the video -- sometimes it also gives some cryptic error code, sometimes it doesn't, and some other times it just locks up hard.

Interestingly. using the bitrate of 1500kbps this happens about 7 - 8 minutes into the whole video (30 sec into one chapter, 6). The real strange thing is that using any other bitrates it doesn't even start playing said chapter (6), or dies a few seconds into it. On the other hand a different chapter (ch8) encodes and plays fine with many different bitrates, and dies only when it gets really high like 2000kbps.

Anyone has an explanation for this? I could understand that with an underpowered CPU high bitrates or certain CPU intensive features such as CABAC entropy encoding would have a detrimental effect, but movies are completely unplayable when I turn CABACoff and use CAVLC instead. (all movies play fine in VLC or mplayer, so it's not just simply a bad encoding)

Another thing I noticed, all of the video players ( Act 1, pre-installed [Movies], mVideoPlayer ) seem to use the very same decoder since they all behave identically, so all they do is just provide the user interface and hooks to some library routines, meaning that writing a video player probably doesn't require a whole lot of effort.
 

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Hmmm, I guess I may be the only one trying to use the T301 as a 7" portable video player?
Well you might be the only T301 video user but you also have a T103 user sitting right beside his 2 year old son who is watching Bubble Guppies... on the tablet as I type this on the laptop.

I'm not sure of the best video resolution for your needs but I have a suggestion that might give you some ideas without too much trouble.

I've downloaded a lot of Youtube kids shows using Tubemate - site link here:
Tube Mate

All you do is open the program and search for a kids video - my son likes watching the UK show called "Postman Pat" and has about 10 of the episodes on the tablet.

Anyway once you find the video that you want to watch you get a pop up which allows you to choose the resolution for the saved video file. Try different resolutions and see what works best on the T301. I have to say that the video quality is generally very good indeed.
 

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Interestingly. using the bitrate of 1500kbps this happens about 7 - 8 minutes into the whole video (30 sec into one chapter, 6). The real strange thing is that using any other bitrates it doesn't even start playing said chapter (6), or dies a few seconds into it.
I've not got reference to back this up but I thought that with our tablets it was better to use video encoded at less than 1000kbps?
 

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Discussion Starter · #6 ·
Looking at the setings and recommendations,
  • MP4 file format
  • Video Codec: H.264
  • Framerate: 15FPS or 24 FPS
  • 16:9 - 800x480
  • 4:3 - 800x600
  • Zero Crop
  • Audio Codec: AAC
  • Stereo
  • Samplerate (kHz): 44.1
  • Bitrate (Kbps): 160
  • Smaller file size is better
I have a feeling they didn't do a whole lot testing. First, they don't have any recommended bitrate -- a major oversight, IMHO. Second, most of the tools I've tried didn't allow upsample 720 to 800, so with DVD quality media, one is normally restricted to 720 by N where N is some reasonable number such as 480. Audio works just fine at 48 kHz 192 kbps, so I think no downconversion is needed. And framerate is kinda suspicious, too. What I'd like to know is the hardware's capability -- I've tried 15, 20, 24, and 30, and they all seem to work. Lastly, I was having much-much more problems playing files generated by handbrake than by mencoder.

BTW, one resolution that completely fills the screen without any border is 720x540. Unfortunately, widescreen movies scaled to that look a bit (?!) skewed, though it should be fine with older, 3:2 aspect ratio movies.
 

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Discussion Starter · #8 ·
I'll look into subtitles on my next encode.

As for the kbps rating, The T301 is capable of playing movies with a much higher bitrate than 900 kbps. The one I just tested right now is 1197 kbps (as per GSpot) and it finished playing without any problem. On some individually encoded chapters the T301 was playing fine 1500 kbps or higher bitrate material.
 

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I've done some more testing trying to find the best settings for videos. I eventually plan to make a guide about video encoding for the T301 with mencoder, but until then here are some preliminary results and recommendations.

a] movies encoded as divx / xvid (MPEG 4 part 2) can be played on the T301 even when the bitrate is 3000 (!!!) kbps, yes, that's three thousand kbps, and it's not a typo.
b] movies encoded with h264 (MPEG 4 part 10) can go up to about 1200 - 1500 kbps, but they're prone to randomly crash the Android media server unless the bitrate is below 800 - 1000 kbps
c] movies should be always scaled to fit at least one dimension of the 800x600 display -- if they're smaller, the software inside the T301 will scale them to fit as much as possible
i) non-wide screen movies (4:3) should normally be scaled to 800x600 , i.e: "-vf scale=800:600,harddup"
ii) wide screen movies (16:9 or 16:10) should be scaled to 800x480, or whatever the cropped reolution of the source may be, i.e.: "-vf scale=800:480,harddup", or "-vf crop=720:464:0:8,scale=800:464,harddup" ( it's best to scale wide screen movies only on the horizontal axis)
d] movies that has black bars on any side (usually on top and on bottom of wide screen movies) should be cropped before encoding. The necessary cropping can be determined by "mplayer filename -vf cropdetect", output is like:" [CROP] Crop area: X: 6..715 Y: 0..479 (-vf crop=704:480:10:0)" or "[CROP] Crop area: X: 0..719 Y: 0..477 (-vf crop=720:464:0:8 )
 

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a] movies encoded as divx / xvid (MPEG 4 part 2) can be played on the T301 even when the bitrate is 3000 (!!!) kbps, yes, that's three thousand kbps, and it's not a typo.
I found this very interesting. As it happens, I have a number of avi videos I had encoded at 800x600 for my Nokia N770 using an mencoder-based script called avi-recode-2pass.sh, which is available at various places around the web. (FWIW, I specified "n770" as the target when I encoded them.) I don't know whether they're "optimal" but I discovered they play fairly well on my T301 Cruz. I decided to compare the same video in both mp4 (using Handbrake) and avi (using avi-recode-2pass.sh), playing both versions in MX Player. MX Player can use the hardware decoder, just like all the other video players, or it can use its own software decoder.

- Playing the mp4 file using the hardware decoder, the video froze every 5-10 minutes. Same as all the others. Bleah!
- Playing the mp4 file using the software decoder made the sound go "bz bz-bz-bz bz bz-bz bz." Bleah!
- Playing the avi file using the hardware decoder, the video froze after 36 minutes. Not quite so bleah, but still bleah!
- Playing the avi file using the software decoder, sound was good and the entire 40-minute video played without freezing, and ten minutes or so of the next video played as well before I stopped it. Yay!

Not exhaustive research, just a single video tested. Still, something to consider.

I also like avi-recode-2pass.sh better than Handbrake for a couple other reasons. For one, it's faster than Handbrake, and for another, my main computer at home is an ARM-based Dockstar, and Handbrake comes in binary-only format, exclusively for Intel-based machines. Mencoder comes with all flavors of Linux, and it works fairly well on my Dockstar.
 
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