[MEncoder-users] making movies from jpg's

[Reimar Döffinger]

On Sun, Jan 19, 2014 at 06:25:11PM +0100, Django [BOfH] wrote:
> Hello,
> 
> I've got two weatherwebcams (http://webcam.nausch.org). From 4:00 am
> to 10:59 pm the cam makes every minute a picture. at the end of a day
> so I've 1140 pictures. If the light outside is to dark, the cam's
> produce grayscale pictures, at "normal light" the cam's produce color
> picture.
> 
> If I try to make my movie with:
> 
> /usr/bin/mencoder mf://*.jpg -mf w=1920:h=1080:fps=25:type=jpg \
>                   -ovc lavc -lavcopts vcodec=mjpeg -oac copy \
>                   -force-avi-aspect 1.78:1 -o output.avi

Note that specifying w and h is more likely to break things than help anything,
and type at least should not be necessary, and -oac copy makes little
sense since there is no audio in the first place.

> mencoder is crashing with a segmentation fault. :(

No crash for me, one grayscale jpeg (encoder as gray) and one with
colour, output is an AVI with a gray (encoded as colour though) and a colour image
(contrary to the output I don't think there is a 3rd frame):

MEncoder UNKNOWN-4.8 (C) 2000-2014 MPlayer Team
success: format: 16  data: 0x0 - 0x0
MF file format detected.
[mf] search expr: *.jpg
[mf] number of files: 2 (16)
VIDEO:  [IJPG]  1920x1080  24bpp  25.000 fps    0.0 kbps ( 0.0 kbyte/s)
[V] filefmt:16  fourcc:0x47504A49  size:1920x1080  fps:25.000  ftime:=0.0400
libavcodec version 55.48.101 (internal)
Opening video filter: [expand osd=1]
Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffmjpeg] vfm: ffmpeg (FFmpeg MJPEG)
==========================================================================
Could not find matching colorspace - retrying with -vf scale...
Opening video filter: [scale]
Movie-Aspect is 0.75:1 - prescaling to correct movie aspect.
[swscaler @ 0x7f6ad6ad51e0]bicubic scaler, from gray to yuv420p using MMXEXT
videocodec: libavcodec (1224x1632 fourcc=47504a4d [MJPG])
Writing header...
ODML: vprp aspect is 16384:9204.
Writing header...
ODML: vprp aspect is 16384:9204.
Pos:   0.0s      1f (100%)  0.00fps Trem:   0min   0mb  A-V:0.000 [0:0]
Movie-Aspect is 0.75:1 - prescaling to correct movie aspect.
Pos:   0.1s      2f (100%)  0.00fps Trem:   0min   0mb  A-V:0.000 [0:0]

Skipping frame!
Pos:   0.1s      3f (100%)  0.00fps Trem:   0min   0mb  A-V:0.000 [0:0]

Flushing video frames.
Writing index...
Writing header...
ODML: vprp aspect is 16384:9204.

Video stream: 55468.102 kbit/s  (6933512 B/s)  size: 554681 bytes  0.080 secs  3 frames