Hello world.. and world.. and world... twobobs tips

[twobob]

me@minty16 / $ ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt gray -s 608x800 -i data.raw -f image2 -vcodec mjpeg frame.jpeg

ffmpeg version 0.8.12-6:0.8.12-0ubuntu0.13.10.1, Copyright (c) 2000-2014 the Libav developers
built on Jun 10 2014 15:38:48 with gcc 4.8.1
*** THIS PROGRAM IS DEPRECATED ***
This program is only provided for compatibility and will be removed in a future release. Please use avconv instead.
[rawvideo @ 0x8240c80] Estimating duration from bitrate, this may be inaccurate
Input #0, rawvideo, from 'data.raw':
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0.0: Video: rawvideo, gray, 608x800, 25 tbr, 25 tbn, 25 tbc
Incompatible pixel format 'gray' for codec 'mjpeg', auto-selecting format 'yuvj420p'
[buffer @ 0x824b340] w:608 h:800 pixfmt:gray
[avsink @ 0x8241180] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'out'
[scale @ 0x824a8c0] w:608 h:800 fmt:gray -> w:608 h:800 fmt:yuvj420p flags:0x4
Output #0, image2, to 'frame.jpeg':
Metadata:
encoder : Lavf53.21.1
Stream #0.0: Video: mjpeg, yuvj420p, 608x800, q=2-31, 200 kb/s, 90k tbn, 25 tbc
Stream mapping:
Stream #0.0 -> #0.0
Press ctrl-c to stop encoding
[image2 @ 0x8249860] Could not get frame filename number 2 from pattern 'frame.jpeg'
av_interleaved_write_frame(): Input/output error

errors can be safely ignored.

This converts kindle touch and paperwhite raw framebuffer to JPG in one command

(8 bit only)

[twobob]

logical evolution:

grab.sh: <kindle-ip e.g 192.168.1.70> [Trim Y max]
ssh root@"$1" cat /dev/fb0 | ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt gray \
-s `ssh root@"$1" eips -i | grep xres_virtual | \
[ $# > 1 ] && -v arg=$2 awk '{print$2"x"arg}' || awk '{print$2"x"$4}'` \
-i - -f image2 -vcodec mjpeg kindle-$1-`date +%s`.jpeg

Should detect framebuffer size and performs pull request simultaneously.
Also assign a unique name based on time and IP. handles 3rd arg via ternary


One slight problem on some KT there is a 608x3584 virtual buffer and a 600x800 actual specification.

on the PW even bigger...

Variable framebuffer info
xres: 758 yres: 1024
xres_virtual: 768 yres_virtual: 6144

I think the simple script with an extra arg allowing to trim on the Y would be a nice facility on the average linux box with ffmpeg. not sure but this might be fun on the kindle, there is probably an easier way

command <kindle-ip> [y-max]

would be a lot simpler than the current screenie faffing I do.

but to keep things simple

ssh root@demo cat /dev/fb0 | ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt gray -s `ssh root@demo eips -i | grep xres_virtual | awk '{print$2"x"800}'` -i - -f image2 -vcodec mjpeg out.jpeg

works as a nice one liner.

and if you know what it is you want...

export IP="192.168.1.77" && ssh root@"$IP" cat /dev/fb0 | ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt gray -s 768x1024 -i - -f image2 -vcodec mjpeg out.jpeg

[knc1]

ah, there was an interesting post while you where gone - try this:

grab screen layout data
rotate: portrait -> landscape -> portrait
grab screen layout data

Duh?
Who changed the screen?

I don't recall which model / which firmware - but it was really weird.

[NiLuJe]

@knc1: I think it was on a K4, with its weird not-really-a-K3-but-not-really-a-K5-either kernel module.

@twobob: There was an (old) tool called fbgrab that was built for that, but AFAIR, it didn't support the fb format used on the Kindle. I also vaguely remember someone doing a quick'n dirty C (I think?) version of something similar on a GitHub project. (Whoo, vague hints galore! ).

EDIT: Eh. I think that's what you were referring to here .