Video Player

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Not a proper 'app' page, just an overview of my understanding. --[[User:Speedevil|Speedevil]] 17:39, 16 February 2007 (CET)
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Not a proper 'app' page, just an overview of my understanding.  
 +
--[[User:Speedevil|Speedevil]] 14:44, 1 July 2008 (UTC)
  
 
----
 
----
  
Video is problematic.
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Video is problematic on both GTA01 and GTA02 (freerunner) though for different reasons.
  
 +
==GTA01/Neo1973==
 
On the minus side.
 
On the minus side.
 
*The CPU is certainly not fast enough to decode 480*640 video.
 
*The CPU is certainly not fast enough to decode 480*640 video.
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*Re-encoding video to rotate it, and scale to 320*240, and encoding with a low CPU use codec such as MPEG-1 may well make half-screen doubled videos playable at 25fps.
 
*Re-encoding video to rotate it, and scale to 320*240, and encoding with a low CPU use codec such as MPEG-1 may well make half-screen doubled videos playable at 25fps.
 
*If not, then it almost certainly will be possible at 12fps.
 
*If not, then it almost certainly will be possible at 12fps.
 +
 +
==GTA02/FreeRunner==
 +
On the positive side.
 +
* The Glamo chip can do scaling, rotation, this means that the CPU does not have to do this, and it's more flexible than simply setting the LCD to half resolution.
 +
* The Glamo can decode mpeg-4.
 +
 +
===Negatives===
 +
Unfortunately, it brings huge negatives, which may in some cases outweigh these.
 +
 +
* The bandwidth to it is only 7 megabytes/second, and this is shared with the SD.
 +
* It can only decode mpeg-4, any other format will need to be decoded on the CPU, and pushed over the very slow bus.
 +
* The 7 megabytes/second figure uses 100% of CPU. If you need 50% of CPU to decode video, then you only have 3.5 megabytes/second.
 +
** It's not even this good, as you need to subtract IO to the SD card from the total bandwidth.
 +
 +
===Summary===
 +
It should play easily mpeg-4 (640*480*15fps and 320*240*30FPS), however other formats will require transcoding.
 +
 +
-In common-
 +
 
*Playing most very small - postage stamp - videos as are sent by many phones should be possible.
 
*Playing most very small - postage stamp - videos as are sent by many phones should be possible.
*1G of storage should give several hours of mpeg4 video, as the quality can be reduced somewhat without being visible on the screen.
+
*4G of storage should give many hours of mpeg4 video, as the quality can be reduced somewhat without being visible on the screen.
  
 +
=Reports of GTA01=
 
From a conversation with XorA, in the [irc://freenode.com/#openmoko IRC channel].
 
From a conversation with XorA, in the [irc://freenode.com/#openmoko IRC channel].
  

Revision as of 15:44, 1 July 2008

Not a proper 'app' page, just an overview of my understanding. --Speedevil 14:44, 1 July 2008 (UTC)


Video is problematic on both GTA01 and GTA02 (freerunner) though for different reasons.

Contents

GTA01/Neo1973

On the minus side.

  • The CPU is certainly not fast enough to decode 480*640 video.
  • The display is portrait, which means that an additional rotation step is needed for most landscape video, adding to CPU usage.
  • Downloading an arbitrary video, and playing it without transcoding it, then playing it later will not be possible.

However.

On the positive side.

  • The LCD can be switched to a 240*320 stretch mode, which is much less taxing.
  • Re-encoding video to rotate it, and scale to 320*240, and encoding with a low CPU use codec such as MPEG-1 may well make half-screen doubled videos playable at 25fps.
  • If not, then it almost certainly will be possible at 12fps.

GTA02/FreeRunner

On the positive side.

  • The Glamo chip can do scaling, rotation, this means that the CPU does not have to do this, and it's more flexible than simply setting the LCD to half resolution.
  • The Glamo can decode mpeg-4.

Negatives

Unfortunately, it brings huge negatives, which may in some cases outweigh these.

  • The bandwidth to it is only 7 megabytes/second, and this is shared with the SD.
  • It can only decode mpeg-4, any other format will need to be decoded on the CPU, and pushed over the very slow bus.
  • The 7 megabytes/second figure uses 100% of CPU. If you need 50% of CPU to decode video, then you only have 3.5 megabytes/second.
    • It's not even this good, as you need to subtract IO to the SD card from the total bandwidth.

Summary

It should play easily mpeg-4 (640*480*15fps and 320*240*30FPS), however other formats will require transcoding.

-In common-

  • Playing most very small - postage stamp - videos as are sent by many phones should be possible.
  • 4G of storage should give many hours of mpeg4 video, as the quality can be reduced somewhat without being visible on the screen.

Reports of GTA01

From a conversation with XorA, in the IRC channel.

400kbps mpeg4 works on a 200Mhz neo (without sound) on prerotated 240*320 ffmpeg codec videos, at 25fps, using stock mplayer.

With sound, this drops to 18fps.

There are optimisations for mplayer that look promising to get 25fps with sound.

For switching between QVGA and VGA mode do the following with a compatible kernel:

chvt 4 && echo qvga-normal > /sys/devices/platform/s3c24xx-spi-gpio.1/spi0.0/state && fbset qvga

vice versa:

echo normal > /sys/devices/platform/s3c24xx-spi-gpio.1/spi0.0/state && fbset vga && chvt 3

taken from http://lists.openmoko.org/pipermail/neo1973-hardware/2007-October/000267.html

To make your videos/DVDs neo1973 compatible use mencoder like this: Find out the -vf cropping parameters with

mplayer input.avi -vf cropdetect

let it run a few seconds and insert the given cropping values into this command

mencoder input.avi -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=300 -vf crop=xx:xx:xx:xx,rotate=2,scale=-2:320 -oac mp3lame -lameopts br=64:cbr -o output2.avi

To encode a DVD first find out the -vf cropping parameters with

mplayer -dvd-device /path/to/dvd dvd:// -vf cropdetect -sb 50000000

let it run a few seconds and insert the given cropping values into this command

mencoder -dvd-device /path/to/dvd dvd:// -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=300 -vf crop=xx:xx:xx:xx,rotate=2,scale=-2:320 -oac mp3lame -lameopts br=64:cbr -o output.avi

This will rotate the video/DVD, scale it and encode it to mpeg4 with a bitrate of 300kBit/s. Works like a charm.

To avoid console blanking type

echo -e '\033[9;0]' > /dev/ttyX

where 'X' is your terminal number - for example if you did chvt 4 then /dev/tty4 is your terminal.

To avoid kernel output in vt do

echo 0 > /proc/sys/kernel/printk

Playback using 480x640 / 640x480

To get best speed on GTA01 (best size-speed-resolution-codec trade-off I could find - doesn't mean it's perfect though) crosscode using:

mencoder <sourcefile> -o <targetfile.avi> -ofps 13 -vf scale -zoom -xy 240 -af channels=1:0:0:1:0 -oac lavc -ovc lavc -lavcopts acodec=mp3:vcodec=h263p:autoaspect=1:vbitrate=300:abitrate=32

Also working okay:

mencoder <sourcefile> -o <targetfile.avi> -ofps 13 -vf scale -zoom -xy 352 -af channels=1:0:0:1:0 -oac lavc -ovc lavc -lavcopts acodec=mp3:vcodec=h263p:autoaspect=1:vbitrate=200:abitrate=32

You can playback the file using:

mplayer -sws 0 -nodouble -vo sdl -fs -framedrop <tagetfile.avi>

You may also want to use:

-autosync 30 -vf scale -zoom -xy 640 -vf rotate=1
Personal tools

Not a proper 'app' page, just an overview of my understanding. --Speedevil 14:44, 1 July 2008 (UTC)


Video is problematic on both GTA01 and GTA02 (freerunner) though for different reasons.

GTA01/Neo1973

On the minus side.

  • The CPU is certainly not fast enough to decode 480*640 video.
  • The display is portrait, which means that an additional rotation step is needed for most landscape video, adding to CPU usage.
  • Downloading an arbitrary video, and playing it without transcoding it, then playing it later will not be possible.

However.

On the positive side.

  • The LCD can be switched to a 240*320 stretch mode, which is much less taxing.
  • Re-encoding video to rotate it, and scale to 320*240, and encoding with a low CPU use codec such as MPEG-1 may well make half-screen doubled videos playable at 25fps.
  • If not, then it almost certainly will be possible at 12fps.

GTA02/FreeRunner

On the positive side.

  • The Glamo chip can do scaling, rotation, this means that the CPU does not have to do this, and it's more flexible than simply setting the LCD to half resolution.
  • The Glamo can decode mpeg-4.

Negatives

Unfortunately, it brings huge negatives, which may in some cases outweigh these.

  • The bandwidth to it is only 7 megabytes/second, and this is shared with the SD.
  • It can only decode mpeg-4, any other format will need to be decoded on the CPU, and pushed over the very slow bus.
  • The 7 megabytes/second figure uses 100% of CPU. If you need 50% of CPU to decode video, then you only have 3.5 megabytes/second.
    • It's not even this good, as you need to subtract IO to the SD card from the total bandwidth.

Summary

It should play easily mpeg-4 (640*480*15fps and 320*240*30FPS), however other formats will require transcoding.

-In common-

  • Playing most very small - postage stamp - videos as are sent by many phones should be possible.
  • 4G of storage should give many hours of mpeg4 video, as the quality can be reduced somewhat without being visible on the screen.

Reports of GTA01

From a conversation with XorA, in the IRC channel.

400kbps mpeg4 works on a 200Mhz neo (without sound) on prerotated 240*320 ffmpeg codec videos, at 25fps, using stock mplayer.

With sound, this drops to 18fps.

There are optimisations for mplayer that look promising to get 25fps with sound.

For switching between QVGA and VGA mode do the following with a compatible kernel:

chvt 4 && echo qvga-normal > /sys/devices/platform/s3c24xx-spi-gpio.1/spi0.0/state && fbset qvga

vice versa:

echo normal > /sys/devices/platform/s3c24xx-spi-gpio.1/spi0.0/state && fbset vga && chvt 3

taken from http://lists.openmoko.org/pipermail/neo1973-hardware/2007-October/000267.html

To make your videos/DVDs neo1973 compatible use mencoder like this: Find out the -vf cropping parameters with

mplayer input.avi -vf cropdetect

let it run a few seconds and insert the given cropping values into this command

mencoder input.avi -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=300 -vf crop=xx:xx:xx:xx,rotate=2,scale=-2:320 -oac mp3lame -lameopts br=64:cbr -o output2.avi

To encode a DVD first find out the -vf cropping parameters with

mplayer -dvd-device /path/to/dvd dvd:// -vf cropdetect -sb 50000000

let it run a few seconds and insert the given cropping values into this command

mencoder -dvd-device /path/to/dvd dvd:// -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=300 -vf crop=xx:xx:xx:xx,rotate=2,scale=-2:320 -oac mp3lame -lameopts br=64:cbr -o output.avi

This will rotate the video/DVD, scale it and encode it to mpeg4 with a bitrate of 300kBit/s. Works like a charm.

To avoid console blanking type

echo -e '\033[9;0]' > /dev/ttyX

where 'X' is your terminal number - for example if you did chvt 4 then /dev/tty4 is your terminal.

To avoid kernel output in vt do

echo 0 > /proc/sys/kernel/printk

Playback using 480x640 / 640x480

To get best speed on GTA01 (best size-speed-resolution-codec trade-off I could find - doesn't mean it's perfect though) crosscode using:

mencoder <sourcefile> -o <targetfile.avi> -ofps 13 -vf scale -zoom -xy 240 -af channels=1:0:0:1:0 -oac lavc -ovc lavc -lavcopts acodec=mp3:vcodec=h263p:autoaspect=1:vbitrate=300:abitrate=32

Also working okay:

mencoder <sourcefile> -o <targetfile.avi> -ofps 13 -vf scale -zoom -xy 352 -af channels=1:0:0:1:0 -oac lavc -ovc lavc -lavcopts acodec=mp3:vcodec=h263p:autoaspect=1:vbitrate=200:abitrate=32

You can playback the file using:

mplayer -sws 0 -nodouble -vo sdl -fs -framedrop <tagetfile.avi>

You may also want to use:

-autosync 30 -vf scale -zoom -xy 640 -vf rotate=1