Reduce noise?

[oralbertr]

Just purchased the PiCapture HD1 card and installed it in a Pi 3 running latest release of raspberian. I watched the sample promotional videos posted on your website (https://lintestsystems.com/hd1-examples ) and they don’t seem to exhibit *any* noise in 1080p while the videos I’m capturing look nothing like it.

The HDMI signal comes from Panasonic HC V-770 in 1080p 60fps and looks beautiful on HDMI monitor without any noise. Is there any way to tweak card’s or raspivid’s parameters to reduce the noise? What am I doing wrong?

Here are the two 20 seconds sample clips. Camera is static and not moving. Colors seems to be over-saturated, with sa -35 parameter they look closer to the ones on HDMI monitor. Take a look at the pot and bottom of the soccer ball to see what I mean. Is there anything that can be done to reduce it?

pi@pi:~ $ uname -a
Linux pi 4.9.41-v7+ #1023 SMP Tue Aug 8 16:00:15 BST 2017 armv7l GNU/Linux
pi@pi:~ $
pi@pi:~ $ pivideo -q all -v
PiVideo Version 1.12
Port used for video processor is: i2c1
PiCapture HD1 is ready
Active video: Mode 1
Selected video source is: auto
Active video source is: hdmi
Raspberry Pi camera port is not active
Frame skip is Off
Video processor firmware version: 05-85C103
Video processor hardware id: 18A4660010429880
pi@pi:~ $
pi@pi:~ $ raspivid -md 1 -w 1920 -h 1080 -awbg 1.0,1.0 -awb off -ex off -t 20000 -n -o test_sa000.h264
pi@pi:~ $ raspivid -md 1 -w 1920 -h 1080 -awbg 1.0,1.0 -awb off -ex off -t 20000 -sa -35 -n -o test_sa-35.h264
pi@pi:~ $

Default saturation
Saturation -35

-albertr

• This topic was modified 2 years, 11 months ago by oralbertr.

[mwlinder]

One possible source for this noise is the settings used for H.264 encoding. You could try changing the profile or capturing at a higher bitrate.

Depending on your application, another possibility is to capture at 1080p but scale the output to a lower resolution. This can also have a significant effect on the kind of “jitter” noise you are seeing.

[oralbertr]

Thank you for suggestions. I did couple of test recording comparing 720p vs 1080p using two Roku streaming players and while 720p looks fine, 1080p seem to have the problem too (i.e. colors gradient on Roku’s background ). I’m not convinced that I need to capture in 1080p, I think I would be happy with quality of 720p if I can make my Panasonic camcorder to output video at that resolution.

1080p
720p

-albertr

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