[vox-tech] Broken video? Poor frame rate

[Peter Salzman]

Hi All,

I recorded a Skype video chat with Evaer   The chat was with someone
in Italy, so the quality of the chat was poor, but the video recording
is horrendous.  Much poorer than the chat.

While chatting I could discern the individual frames.  It kinda sorta
looked smooth if I didn't scrutinize it too much.

However, when I play the video, the frames are DEFINITELY discrete --
the video is basically audio with a picture that changes every .5 to 2
seconds.  Much, much poorer than the chat.

I've tried on Linux and Windows, which are 4 core Nehalem and 8 core
Sandybridge systems with 8 GB of RAM and SSD hard drives. and the
video sucks on both. The quality of the video is definitely much
poorer than the chat itself, so I'm thinking maybe the video is either
broken or in bad need of better compression.  ffmpeg reports:


p at satan$ ffmpeg -i darionapoli74_2013-08-09_12-36-46.mp4
ffmpeg version 0.8.6-4:0.8.6-0ubuntu0.12.04.1, Copyright (c) 2000-2013
the Libav developers

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'darionapoli74_2013-08-09_12-36-46.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    creation_time   : 1970-01-01 00:00:00
    encoder         : Lavf52.32.0
  Duration: 01:05:16.23, start: 0.000000, bitrate: 350 kb/s
    Stream #0.0(eng): Video: h264 (Main), yuv420p, 640x480 [PAR 1:1
DAR 4:3], 292 kb/s, 28.26 fps, 30 tbr, 30 tbn, 60 tbc
    Metadata:
      creation_time   : 1970-01-01 00:00:00
    Stream #0.1(eng): Audio: aac, 16000 Hz, stereo, s16, 55 kb/s


I'm no video expert, but I interpret this as there IS video
compression (h264) and audio compression (aac).  Audio sampling is
pretty high quality (it tracks the sucky audio very well) and the fps
is actually quite high, so this points to one of two things:

1. The video file or compression is broken somehow and my computer is
having trouble decoding and displaying the video.

2. Evaer just really, really, really sucks at recording Skype video chats.


I'm leaning towards #2 because my computer's fans don't go on, and the
RAM / CPU utilization are both very low while playing this video.

Still, I'm not 100% sure, because it seems odd that a commercial
product would suck so noticeably bad.  Usually commercial products
suck subtly or if you try using them in a way they were not engineered
to function.  But this was a really plain vanilla recording project.
It should've been a lot better.

Any thoughts?  Much appreciated!

Pete