[SOLVED] Problem converting from rgba to jpg on iOS and OSX
Posted: 2014-11-04T02:57:00-07:00
Hi,
I have an algorithm that takes snapshots from an OpenGL context. For each snapshot, I create an .rgba raw file, just reading the pixels from the buffer.
Then for each rgba file, I use ConvertImageCommand() to convert to jpeg. This commands works fine for the majority of the files, but it always fails with the 8th file I try to convert. Then it keeps doing it fine.
The specific parameters I'm using are:
The error I get in the exception is:
I'm using ImageMagick for iOS, version 6.8.8-9.
If I download the rgba files from the iPad to the Mac, and use the convert command with the verbose option, I can see that ImageMagick is treating the input image as PCX, and not as RGBA, like the rest of the files.
In spite of telling the size, ImageMagick is using 1x1. Also, PCX format, instead of RGBA.
With the next file, the conversion is fine:
The ImageMagick version on my Mac is also 6.8.8-9.
Does any of this tell you something?
EDIT: The raw file is just fine. I can open it with Photoshop, specifying the size:
SOLVED: Apparently I had to prepend "RGBA:" to the input file. Now it works.
Thanks,
Robert.
I have an algorithm that takes snapshots from an OpenGL context. For each snapshot, I create an .rgba raw file, just reading the pixels from the buffer.
Then for each rgba file, I use ConvertImageCommand() to convert to jpeg. This commands works fine for the majority of the files, but it always fails with the 8th file I try to convert. Then it keeps doing it fine.
The specific parameters I'm using are:
Code: Select all
convert -size 1512x1532 -depth 8 soruce.rgba dest.jpgCode: Select all
NoImagesDefined `/var/mobile/Containers/Data/Application/4C9DACEC-EF5C-43D3-B122-1B853C19DB84/Library/Caches/TextureCache/converted0.jpg' @ error/convert.c/ConvertImageCommand/3150If I download the rgba files from the iPad to the Mac, and use the convert command with the verbose option, I can see that ImageMagick is treating the input image as PCX, and not as RGBA, like the rest of the files.
Code: Select all
MacBook-Pro-de-Roberto:TextureCache ro$ convert -verbose -size 1512x1532 -depth 8 raw0.rgba converted0.jpg
raw0.rgba PCX 1x1 1x1+0+0 16-bit sRGB 9.266MB 0.000u 0:00.009
raw0.rgba=>converted0.jpg PCX 1x1 1x1+0+0 8-bit sRGB 288B 0.010u 0:00.000
With the next file, the conversion is fine:
Code: Select all
MacBook-Pro-de-Roberto:TextureCache ro$ convert -verbose -size 1512x1532 -depth 8 raw1.rgba converted1.jpg
raw1.rgba RGBA 1512x1532 1512x1532+0+0 8-bit TrueColor sRGB 9.266MB 0.020u 0:00.039
raw1.rgba=>converted1.jpg RGBA 1512x1532 1512x1532+0+0 8-bit sRGB 408KB 0.120u 0:00.119
Does any of this tell you something?
EDIT: The raw file is just fine. I can open it with Photoshop, specifying the size:
SOLVED: Apparently I had to prepend "RGBA:" to the input file. Now it works.
Thanks,
Robert.