[android-developers] Re: Android renders RGB values wrong.
Hi, I face the same issue with OpenGL texture. I use gradient texture and this one was damaged due to convertion from 24bit = 565. To solve this issue I embeded libpng in my application using NDK. You said that the screen is 565 so we loose precision : Yes but in OpenGL, glEnable(GL_DITHER) will dither the colors. So(in that case) why doing OpenGL job ? Colors convertion should be done by the final renderer : it is the only one to know the final screen config. I think this image convertion at loading should be optional. Because it depends in which context you use it. Finally, with the dither I don't have color steps due to downsampling. Best Regards On 3 mai, 00:27, Dianne Hackborn hack...@android.com wrote: If the issue is losing precision due to a 16bpp screen with 565 colors, changing it to 256 colors won't necessarily help since each of those colors are still full 888. On Mon, May 2, 2011 at 2:52 PM, Andrew Huang proelited...@gmail.com wrote: Another way is to make your images have 256 color at most. You can do this in Gimp by changing the mode to indexed in the image menu, and setting the maximum color. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: Android renders RGB values wrong.
You don't need to use libpng to load a 24 bit image. Just set the bitmap option to specify you want higher bit depth when loading it. On Fri, May 13, 2011 at 8:16 AM, cg-dev charles.gorand@gmail.comwrote: Hi, I face the same issue with OpenGL texture. I use gradient texture and this one was damaged due to convertion from 24bit = 565. To solve this issue I embeded libpng in my application using NDK. You said that the screen is 565 so we loose precision : Yes but in OpenGL, glEnable(GL_DITHER) will dither the colors. So(in that case) why doing OpenGL job ? Colors convertion should be done by the final renderer : it is the only one to know the final screen config. I think this image convertion at loading should be optional. Because it depends in which context you use it. Finally, with the dither I don't have color steps due to downsampling. Best Regards On 3 mai, 00:27, Dianne Hackborn hack...@android.com wrote: If the issue is losing precision due to a 16bpp screen with 565 colors, changing it to 256 colors won't necessarily help since each of those colors are still full 888. On Mon, May 2, 2011 at 2:52 PM, Andrew Huang proelited...@gmail.com wrote: Another way is to make your images have 256 color at most. You can do this in Gimp by changing the mode to indexed in the image menu, and setting the maximum color. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: Android renders RGB values wrong.
I know, but in Eclair it's not working. If you put Bitmap option to RGBA. You get a RGBA image but the image is altered. Maybe I'm wrong, but I remember I face this issue on my Eclair phone and take this workaround using libpng. In eclair release, if the bitmap has no alpha it was converted to 565. SkImageDecoder_libpng.cpp ~ l.277 I face this issue severals month ago and I remember I have trace down to Skia and found the issue but I don't keep my notes on this subject. Anyway seems fixed in Gingerbread. Regards. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
Actually that didn't went well. I downsampled my images to 256 colors in gimp, and they displayed correctly afterwards. Even 4096 colors was giving me trouble. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
Another way is to make your images have 256 color at most. You can do this in Gimp by changing the mode to indexed in the image menu, and setting the maximum color. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: Android renders RGB values wrong.
If the issue is losing precision due to a 16bpp screen with 565 colors, changing it to 256 colors won't necessarily help since each of those colors are still full 888. On Mon, May 2, 2011 at 2:52 PM, Andrew Huang proelited...@gmail.com wrote: Another way is to make your images have 256 color at most. You can do this in Gimp by changing the mode to indexed in the image menu, and setting the maximum color. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
I gave up trying to solve the problem. My current solution is to use a small patch of the color that I want to use as the background to make a tiled background. On Apr 26, 5:38 pm, Mark Wyszomierski mar...@gmail.com wrote: Not all devices use 24-bit color buffers. Some are 16-bit Good point. I saw this on the N1, nexus S for sure, can't remember where else I saw it. On Apr 26, 5:08špm, Kostya Vasilyev kmans...@gmail.com wrote: PNG is lossless, it's basically LZW or something similar applied on a per-block basis, IIRC. JPG is the lossy one. The build tools do perform some image optimizations, but, as far as I know, they don't change color values. 27.04.2011 1:04 ÐÏÌØÚÏ×ÁÔÅÌØ lbendlin l...@bendlin.us ÎÁÐÉÓÁÌ: png is lossy, right? What if you use a lossless format? -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
I've seen render issues like this. I think one example was putting a png with a flat color next to a view with its background color specified with the same hex value. They won't match. It makes it really difficult to make portions of your layout blend together. Example: ImageView android:src=@drawable/flat_grey_ffebebeb_png / LinearLayout android:background=ffebebeb / I'm sure the png I created has the same hex value as the manually specified background value. Not sure why they don't match when you run, but, that's what it is. Mark On Apr 18, 11:48 am, Andrew Huang proelited...@gmail.com wrote: Specify a RGB, i.e, color name=test_color#ff292728/color. Use the a Color Meter tool on Windows or Mac to sample the color in the Layout Preview screen. You'll see that it renders the correct value of 292728. Sampling the same color in the emulator would return a different value, #282329. This is causing us some serious problems with our graphics (i.e. images are not correctly blending with the background), so we would like to understand what's going on. My searches have turned up nothing so far. If anyone has a deeper understanding of how colors are render, we would greatly appreciate the help. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: Android renders RGB values wrong.
Not all devices use 24-bit color buffers. Some are 16-bit, and you might want to adjust the colors accordingly. 27.04.2011 0:48 пользователь Mark Wyszomierski mar...@gmail.com написал: I've seen render issues like this. I think one example was putting a png with a flat color next to a view with its background color specified with the same hex value. They won't match. It makes it really difficult to make portions of your layout blend together. Example: ImageView android:src=@drawable/flat_grey_ffebebeb_png / LinearLayout android:background=ffebebeb / I'm sure the png I created has the same hex value as the manually specified background value. Not sure why they don't match when you run, but, that's what it is. Mark On Apr 18, 11:48 am, Andrew Huang proelited...@gmail.com wrote: Specify a RGB, i.e, color name=test_color#ff292728/color. Use the a Color Meter tool on Windows or Mac to sample the color in the Layout Preview screen. You'll see that it renders the correct value of 292728. Sampling the same color in the emulator would return a different value, #282329. This is causing us some serious problems with our graphics (i.e. images are not correctly blending with the background), so we would like to understand what's going on. My searches have turned up nothing so far. If anyone has a deeper understanding of how colors are render, we would greatly appreciate the help. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
png is lossy, right? What if you use a lossless format? -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: Android renders RGB values wrong.
PNG is lossless, it's basically LZW or something similar applied on a per-block basis, IIRC. JPG is the lossy one. The build tools do perform some image optimizations, but, as far as I know, they don't change color values. 27.04.2011 1:04 пользователь lbendlin l...@bendlin.us написал: png is lossy, right? What if you use a lossless format? -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: Android renders RGB values wrong.
Not all devices use 24-bit color buffers. Some are 16-bit Good point. I saw this on the N1, nexus S for sure, can't remember where else I saw it. On Apr 26, 5:08 pm, Kostya Vasilyev kmans...@gmail.com wrote: PNG is lossless, it's basically LZW or something similar applied on a per-block basis, IIRC. JPG is the lossy one. The build tools do perform some image optimizations, but, as far as I know, they don't change color values. 27.04.2011 1:04 пользователь lbendlin l...@bendlin.us написал: png is lossy, right? What if you use a lossless format? -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
