I enabled log in enigma.
I want to emphasize that I have sh4 receiver and I do not have the original openpli enigma, but I see that I have exactly the same problem, and my png images look exactly the same as in the original.
As I wrote earlier problems is with png thumbnails. When the images open then everything is ok. If for displaying used data from Thumbnails folder, then the images are displayed incorrectly.
My youtube plugin for image display used data which are stored in the variable, so it is exactly the same problems as with pictures data from Thumbnails folder.
In the log I can see some problems but maybe someone see in it something useful.
Here's the log with my plugin start with incorect images:
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=1.000000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/icon.png
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/icon.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=72 xoff=0 yoff=0 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=1.000000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/Search.png
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=1.000000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/PubFeeds.png
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=1.000000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/MyFeeds.png
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/Search.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=72 xoff=0 yoff=0 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/PubFeeds.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=72 xoff=0 yoff=0 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/MyFeeds.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=72 xoff=0 yoff=0 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
Here's the log when TV picture set 4:3, my plugin start and images are displayed:
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=0.750000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/icon.png
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/icon.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=54 xoff=0 yoff=9 xscale=1.000000 yscale=1.333333 aspect=0.750000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=0.750000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/Search.png
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=0.750000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/PubFeeds.png
[ePicLoad] setPara max-X=100 max-Y=72 aspect_ratio=0.750000 cache=0 resize=1 bg=#00000000 auto_orient=0
[Picload] software decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/MyFeeds.png
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/Search.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=54 xoff=0 yoff=9 xscale=1.000000 yscale=1.333333 aspect=0.750000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/PubFeeds.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=54 xoff=0 yoff=9 xscale=1.000000 yscale=1.333333 aspect=0.750000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/MyFeeds.png
[getData] ox=100 oy=72 max_x=100 max_y=72 scrx=100 scry=54 xoff=0 yoff=9 xscale=1.000000 yscale=1.333333 aspect=0.750000 bits=8 orientation=1
[ePicLoad] decode thread ... got quit msg
Here's the log from picture player when the first time open image to display as a thumbnail. The image is displayed:
[ePicLoad] get Thumbnail... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/HD_videos.png
[ePicLoad] save Thumbnail... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/.Thumbnails/pc_6AFE3F91
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/HD_videos.png
[getData] ox=260 oy=186 max_x=260 max_y=300 scrx=260 scry=186 xoff=0 yoff=57 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=8 orientation=1
[gAccel] accelAlloc called with size 0
Here's the log from picture player for the second time you open the image to display as a thumbnail.
The data for the image is taken from Thumbnails folder and are not displayed correctly:
[ePicLoad] get Thumbnail... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/HD_videos.png
[ePicLoad] Cache File found
[Picload] hardware decode picture... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/.Thumbnails/pc_6AFE3F91
(decode_jpeg_noalloc): pre-scaling to width 192 height 144 from width 180 height 129, macro block limit border width = 12, height = 16
....
(blit_decoder_result): blitting result
(decode_jpeg_noalloc): JPEG decode finished
[ePicLoad] decode finished... /usr/lib/enigma2/python/Plugins/Extensions/YouTube/icons/.Thumbnails/pc_6AFE3F91
[getData] ox=260 oy=186 max_x=260 max_y=300 scrx=260 scry=186 xoff=0 yoff=57 xscale=1.000000 yscale=1.000000 aspect=1.000000 bits=24 orientation=1