Raspberry Pi Forums

Hi all. I just broke out my old (already?!) Model B to tinker with last night; I decided to run it with my 5" 16:9 widescreen display just for fun , but I ran into a speed bump. The last time I used that 5" display was with an older 2014 something raspbian image and I had the config.txt file all setup so that the composite display output would show the right aspect ratio (16:9 for this display) and the overscan was all set perfectly. I have since then wiped all my cards and have put the latest raspbian image onto them. Well so when I went to edit the config.txt file on the new raspbian image, I had to add the 'sdtv_aspect=3' line as usual because it isn't included by default, and I also tweaked the overscan settings a little. I rebooted, and the overscan had changed a little ( I'll have to spend some time fine tuning it), but the aspect ratio won't change ! I have tried changing to various 'sdtv_mode=x' settings and still no luck. I have double and triple checked that aspect line to make sure I spelled it right and even retyped it, but it just won't change to 16:9. Just to clarify, this is all taking place on the latest 2015-2-31 build (I think) of Raspbian on a later version Model B Raspberry Pi. Does anyone have any ideas as to why this aspect ratio setting won't change?

Any help would be greatly appreciated,
BluRazPi

are you really using composite video (through the RCA output connector)?
AFAIK, both PAL and NTSC have fixed aspect ratio's that cannot be changed.

mahjongg wrote:are you really using composite video (through the RCA output connector)?
AFAIK, both PAL and NTSC have fixed aspect ratio's that cannot be changed.

According to http://www.raspberrypi.org/documentatio ... fig-txt.md

You can set it in /boot/config.txt with
sdtv_aspect=1 # 4:3
sdtv_aspect=2 # 14:9
sdtv_aspect=3 # 16:9

Or with
tvservice -c "MODE ASPECT" # for example tvservice -c "PAL 16:9"
or
tvservice --sdtvon="MODE ASPECT"

okay, i did not know that, resolution will stay the same though....

Thats why they sometimes call PAL "576i" because it has a fixed vertical resolution of 576 lines, and is interlaced.
http://en.wikipedia.org/wiki/576i

mahjongg wrote:okay, i did not know that, resolution will stay the same though....

Thats why they sometimes call PAL "576i" because it has a fixed vertical resolution of 576 lines, and is interlaced.
http://en.wikipedia.org/wiki/576i

4:3 will have a different horizontal resolution to 16:9 or 14:9

DougieLawson wrote:4:3 will have a different horizontal resolution to 16:9 or 14:9

My memory may be playing up.

The standard PAL signal only allows signals up to about 5MHz, which gives 700-or-so active pixels across a line, and 575 or 576 active lines.
Whether the display spreads those pixels so they're in a rectangle with some simple relationship between its height and width is not determined by the PAL signal.

There is a signal on the SCART system that can tell the display what to do.

Burngate wrote: Whether the display spreads those pixels so they're in a rectangle with some simple relationship between its height and width is not determined by the PAL signal.

No indeed it is not, and I really doubt, the PI will give out more pixels per line if a widescreen ratio is set up, or am I wrong?
All I ever heard about it is that it would downscale a (which one is still a question to me) HDMI mode to create a PAL or NTSC video resolution.