Icons Are Pretty Right?
I'm working on an UI update in an iOS app, and trying to make things look a bit better with some new icons- but I seem to be incapable of determining how to save an image correctly so that it looks good in the interface!
As you can see from this image, if I include a white background with the image it looks great. If I take those same images and use an alpha background they look terrible! It appears that either the images aren't using the #2x correctly, or something else is going horribly wrong.
These images are either saved with GIMP as a png with alpha, or exported from inkscape, the originals are vector graphics. We get the same results from both avenues. I am using both a base imageName.png and imageName#2x.png for scaling.
Somehow, magically, I changed the a single image to greyscale in gimp, and changed the base size to 25px and it showed up with alpha correctly blended. Stock images from apple are also functioning correctly, so it absolutely seems to be something that I'm doing incorrectly when I'm saving the images.
The Setup in XCode
Basic Questions
Is there a certain bit depth, argb vs rgba format, or some other quirk that I need to know to get these images to show up correctly? Is there any way to verify that the program is loading the correct imageName#2x vs imageName? Is there some document that talks about integrated graphics (the iconography documentation isn't very helpful on technical details)
Actual Images
With Background:
Without Background:
I think you will find success if you just save the image at 4x the size you actually want and specify the size manually.
Related
I am having an issue where the images are rendered with a strange glowing effect around them, pictured here:
It is tough to see from this close but is extremely noticeable when viewing the app. Also, taking these screenshots into a design program and using the color dropper will prove that there is a glow around these images. Each of these images are PDF files, rendered as a template image so that I can change the tintColor instead of adding more images to my assets folder for each color.
I have read some other articles and questions that says there isn't full support for vector graphics yet (here). However, that is outdated as it specifies iOS 7 as the latest version at the time of writing. Now in iOS 13, I assume there have been changes. Another article I read said to never use vector graphics as they can get messed up when Xcode generates PNGs from the PDFs (here).
Information about the assets in my Images.xcassets:
Render as: Template Image
Resizing: Preserve Vector Data
Scales: Single Scale
I also tried to implement 3 PNGs at different sizes (#1x, #2x, #3x) for each image but got the same effect.
Creating new images with a smaller border size got rid of the glow but obviously, that doesn't fit the design style style that I want in an app. I designed these Icons in Sketch and used a border size of 3, then exported as PDF.
So, as I was writing this question I seemed to have found an answer.
It turns out it had nothing to do with anything in Xcode. The problem lies with Sketch. I redesigned each element in Adobe Illustrator, exported them as PDFs, set the same settings in the assets folder like so:
Render as: Template Image
Resizing: Preserve Vector Data
Scales: Single Scale
Here are the updated screenshots:
I am using:
Sketch (Version 52.5)
Adobe Illustrator (Version 24.2.1)
I don't know why this is an issue, but I hope it can help someone who has this issue down the road. If anyone has any more information on this, please write a comment :).
I'm making an app using Swift in Xcode. I have a few buttons and images on one of my View Controllers. I am using high resolution images, but I noticed that they pixelate to the point where it is visible to the naked eye. There are some questions that I have found pertaining to the resizing of images, but none regarding immediate pixelization. I was hoping someone could help. Below are two images. The first is an image (a screenshot) from my app and the second is an image (also a screenshot) from another app that is not mine. The icon on the other app is smaller, but despite this is less pixelated.
have you tried using svg instead of jpg (lossy) or png(lossless)? It would seem that this would be the way to go, since you can expand to perfect definition on all resizing screens. svg uses code instead of an image format that can be lossy and given the examples you have posted would solve your issue.
you can use paint code for more easy worked , with paint code you can export svg
I figured it out. I just had to increase the dpi
I have been looking at SVGKit and I am finding conflicting ideas. Some say it's slower than PNG and others saying it is fast.
I was hoping to get a recommendation and which route I should take. When I am exporting my vector graphics to PNG for display, would it not make sense to use an SVG instead ?
Of course this gives the added value that it remains a vector.
Or is it still recommended in exporting everything to a PNG ?
You might consider the middle-way introduced in Xcode 7. Here you add your assets to the project as vector images (PDF) and at build-time Xcode automatically generates the PNGs in all needed sizes (1x, 2x, 3x).
Personally, I only use SVGs when necessary, like if I need to be able to change the color of the (parts of the) image. I believe there can be a performance hit when resizing vector images at run-time, although Android uses vectors as default, so it might be insignificant.
SVG is most resource intensive and can be used if you need to display something that can be zoomed in and out while PNG should be preferred for most UI graphics (logos, icons, etc.), as it is crisp yet remains lightweight and fast to display so there is no way to compare SVG with PNG in term of Performance.
if you are going after a Crystal clear images you can use pdf based graphics, which are supported by Xcode Using Vector Images in Xcode
if you still need to implement SVGKit i always suggest using some tools (like SVGCleaner) to clean and simplify SVG in order to enhance performance.
I know this isn't a new problem and I've done a full day (literally) of research. I use the latest Xcode 6, and I'm trying to use all PDF files as vector art resources. However, when I export these images from Illustrator in sRGB (sRGB IEC61966-2.1) , these images show up noticeably darker than if I used a png file.
Some previous suggested solutions are: setting Illustrator file color profile to "web" and choose color space "RGB", and exporting to pdf with Illustrator converting the color space to "sRGB IEC61996-2.1". The latter worked for me for one of the images... And today when I tried the same thing it didn't work!
So I tried all the other solutions, I retried, restarted, tried using different programs, renaming resources, cleaning the project... Nothing worked! The colors still look darker on screen, and the old PDF icon I made look perfect still!
The PDF looks perfect in any other viewer, including Xcode itself, by the way. It's when Xcode compiles, the images get broken (PNG files are generated, and something is wrong with their colorspace).
This is driving me nuts... Anyone else having this problem?
Depending on the screen, you can tell that the center button is quite a bit lighter than the other two icons. I intersected two just to show how distinguishable it is. But on my MacBook Air, they appear identical. Perhaps this has to do with what people say about Apple taking the compiling machine's color space into account? On my iPhone and MacBook they look very different.
Update If I change my MacBook Air's display -> color profile to sRGB, I can clearly tell the difference now. I'm retrying importing the PDF,and maybe the conversion will be correct. Will update.
I've had tremendous troubles with this. And I finally figured it out.
Apple uses sRGB for iOS. To do this you must save your pdf (convert to) in sRGB. I do this with Illustrator -> new -> profile = "web", color space = "RGB" -> save as PDF -> (in options) convert to sRGB. This is suggested by many others in similar questions' solutions. The next... Is what I found out. A trap, if you will.
CAUTION! When you copy past paths over to the new artboard in RGB, the RGB values may have been changed by Illustrator. This took me ages to figure out... Even though the saving to PDF part was right, Illustrator broke it by changing the values by default, making everything darker and more dull.
Hope this helps!
I'm using Tesseract OCR 3.01 in my iOS application, it shows 90% accuracy for my data when I pick an image from my phone’s library. But if I use the same image from the camera, it is showing jumbled letters. I followed this tutorial, kindly guide me if something can be done to make sure it works from camera as it works for gallery images.
Yup, There are three things to be specific, First of all, OCR works well with black and white images rather than colored, So If you could try to convert your image to B&W, it would increase accuracy.
The second thing is the size and orientation, You need to force the image to be of 640*480 or 320 size, this would increase both the speed of recognition and the accuracy as well, For orientation , there are a lot of ways to manage.
Finally, If some how you can allow the user to specify Exactly where or on which part of the image he wants to perform the OCR, this greatly increases the accuracy and time since the library does not need to check the entire image for text, rather you already specify the part to be searched for.
PS:I have been working on creating an OCR app for the past few weeks.
Almost for sure the problem is "orientation". Apple tends to create images in one bit map form - the image bits are laid out as if the camera was on its side with the volume buttons top and right. Images that you see which appear taller than wider are still laid out as above, but there is an "orientation" in the EXIF object included with the image.
I'm going to guess that tesseract does not look at the EXIF, but expects the image in a "standard" format so that text is in the position it would be for a person reading the text.
You can test my hypothesis by using camera images taken with volume button top right.
If they work, then what you will need to do is process the image yourself, and re-arrange the bits per the orientation setting. This is not all that hard to do but will require you to read up on vImage and/or bit map contexts.