How to convert a PNG to a WebP in Swift?

I'm trying to convert a PNG image in Webp in Swift, the only framework I got working is OpenCV through Objective-c++.
The problem is that if I resize the image by 512x512 (that's the resolution I need) it crashes:
enter image description here
If I resize the image (either with OpenCV either with Swift) to another resolution (ex 510x510) it doesn't crash.

The strange thing is that on the simulator it never crashes while on the iPhone XS it crashes 90% of the times.

How can I convert a PNG to a Webp in Swift?
Why is OpenCV crashing on the imwrite instruction if the Mat is 512x512?

UPDATE:

OpenCV version: 3.4.2

I found out that this problem happens when the PNG image get processed before from the Core Graphics framework. I need to use it since I save a UIVIew as UIImage this way:

let renderer = UIGraphicsImageRenderer(bounds: bounds)

        return renderer.image { rendererContext in

            layer.render(in: rendererContext.cgContext)

        }

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

Could you, please create a Minimal, Complete, and Verifiable example that reproduces this? (Post it as text, not an image) | What version of OpenCV?

– Dan Mašek
Nov 20 '18 at 22:57

I updated the question

– Danny182
Nov 20 '18 at 23:05

add a comment |

let renderer = UIGraphicsImageRenderer(bounds: bounds)

        return renderer.image { rendererContext in

            layer.render(in: rendererContext.cgContext)

        }

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

Could you, please create a Minimal, Complete, and Verifiable example that reproduces this? (Post it as text, not an image) | What version of OpenCV?

– Dan Mašek
Nov 20 '18 at 22:57

I updated the question

– Danny182
Nov 20 '18 at 23:05

add a comment |

let renderer = UIGraphicsImageRenderer(bounds: bounds)

        return renderer.image { rendererContext in

            layer.render(in: rendererContext.cgContext)

        }

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

let renderer = UIGraphicsImageRenderer(bounds: bounds)

        return renderer.image { rendererContext in

            layer.render(in: rendererContext.cgContext)

        }

ios swift opencv objective-c++

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

edited Nov 20 '18 at 23:04

asked Nov 20 '18 at 22:55

Danny182

1,0371219

asked Nov 20 '18 at 22:55

Danny182

1,0371219

asked Nov 20 '18 at 22:55

Danny182

1,0371219

Could you, please create a Minimal, Complete, and Verifiable example that reproduces this? (Post it as text, not an image) | What version of OpenCV?

– Dan Mašek
Nov 20 '18 at 22:57

I updated the question

– Danny182
Nov 20 '18 at 23:05

add a comment |

Could you, please create a Minimal, Complete, and Verifiable example that reproduces this? (Post it as text, not an image) | What version of OpenCV?

– Dan Mašek
Nov 20 '18 at 22:57

I updated the question

– Danny182
Nov 20 '18 at 23:05

Could you, please create a Minimal, Complete, and Verifiable example that reproduces this? (Post it as text, not an image) | What version of OpenCV?

– Dan Mašek
Nov 20 '18 at 22:57

I updated the question

– Danny182
Nov 20 '18 at 23:05

add a comment |

2 Answers
2

active

oldest

votes

I ended up using another framework to convert PNG to WebP: https://github.com/seanooi/iOS-WebP, had to create the wrapper to use it on swift but it works very good 😊

My wrapper is very simple but does what I needed:

#import <Foundation/Foundation.h>

#import "WebPWrapper.h"

#import "UIImage+WebP.h"



@implementation WebPWrapper

-(NSData *)convertUIImageToWebp:(UIImage *)image :(int)quality {

    NSData *webPData = [UIImage imageToWebP:image quality:quality];

    return webPData;

}

@end

In swift I use it this way:

let webPData = WebPWrapper().convertUIImage(toWebp: image, 90)

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

1

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

|
show 1 more comment

Swift 4.0

pod both 'SDWebImage' AND 'SDWebImage/WebP'

import SDWebImage

if let image_download = UIImage(data: data) {

   let photo:Data = image_download.sd_imageData(as: SDImageFormat.webP)!

}

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

add a comment |

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2 Answers
2

active

oldest

votes

2 Answers
2

active

oldest

votes

I ended up using another framework to convert PNG to WebP: https://github.com/seanooi/iOS-WebP, had to create the wrapper to use it on swift but it works very good 😊

My wrapper is very simple but does what I needed:

#import <Foundation/Foundation.h>

#import "WebPWrapper.h"

#import "UIImage+WebP.h"



@implementation WebPWrapper

-(NSData *)convertUIImageToWebp:(UIImage *)image :(int)quality {

    NSData *webPData = [UIImage imageToWebP:image quality:quality];

    return webPData;

}

@end

In swift I use it this way:

let webPData = WebPWrapper().convertUIImage(toWebp: image, 90)

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

1

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

|
show 1 more comment

I ended up using another framework to convert PNG to WebP: https://github.com/seanooi/iOS-WebP, had to create the wrapper to use it on swift but it works very good 😊

My wrapper is very simple but does what I needed:

#import <Foundation/Foundation.h>

#import "WebPWrapper.h"

#import "UIImage+WebP.h"



@implementation WebPWrapper

-(NSData *)convertUIImageToWebp:(UIImage *)image :(int)quality {

    NSData *webPData = [UIImage imageToWebP:image quality:quality];

    return webPData;

}

@end

In swift I use it this way:

let webPData = WebPWrapper().convertUIImage(toWebp: image, 90)

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

1

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

|
show 1 more comment

I ended up using another framework to convert PNG to WebP: https://github.com/seanooi/iOS-WebP, had to create the wrapper to use it on swift but it works very good 😊

My wrapper is very simple but does what I needed:

#import <Foundation/Foundation.h>

#import "WebPWrapper.h"

#import "UIImage+WebP.h"



@implementation WebPWrapper

-(NSData *)convertUIImageToWebp:(UIImage *)image :(int)quality {

    NSData *webPData = [UIImage imageToWebP:image quality:quality];

    return webPData;

}

@end

In swift I use it this way:

let webPData = WebPWrapper().convertUIImage(toWebp: image, 90)

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

I ended up using another framework to convert PNG to WebP: https://github.com/seanooi/iOS-WebP, had to create the wrapper to use it on swift but it works very good 😊

My wrapper is very simple but does what I needed:

#import <Foundation/Foundation.h>

#import "WebPWrapper.h"

#import "UIImage+WebP.h"



@implementation WebPWrapper

-(NSData *)convertUIImageToWebp:(UIImage *)image :(int)quality {

    NSData *webPData = [UIImage imageToWebP:image quality:quality];

    return webPData;

}

@end

In swift I use it this way:

let webPData = WebPWrapper().convertUIImage(toWebp: image, 90)

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

edited Nov 21 '18 at 13:02

answered Nov 21 '18 at 9:18

Danny182

1,0371219

answered Nov 21 '18 at 9:18

Danny182

1,0371219

answered Nov 21 '18 at 9:18

Danny182

1,0371219

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

1

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

|
show 1 more comment

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

1

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes. - From Review

– Kuldeep
Nov 21 '18 at 12:45

Just added the solution 😊

– Danny182
Nov 21 '18 at 13:07

@Danny182 Hello, I tried this but not working properly. I mean it returns nil image when decode from .webp to png image from Data. Can you please share your example so it can help many of us. Struggling since a week, now you are the only hope!

– iRiziya
Nov 29 '18 at 5:49

For this need I used another library even if I’m sure the one that I used here (iOS-webp) does the same but you need to create the function in the wrapper for that need. If you want you could check the library YYImage. I used that library to decode webp image to data

– Danny182
Nov 29 '18 at 11:35

@Danny182 yeah it helped..Thanks :) Btw..why I get it resultant image with slightly blue shade on it? Any idea? did you face this?

– iRiziya
Nov 30 '18 at 12:08

|
show 1 more comment

Swift 4.0

pod both 'SDWebImage' AND 'SDWebImage/WebP'

import SDWebImage

if let image_download = UIImage(data: data) {

   let photo:Data = image_download.sd_imageData(as: SDImageFormat.webP)!

}

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

add a comment |

Swift 4.0

pod both 'SDWebImage' AND 'SDWebImage/WebP'

import SDWebImage

if let image_download = UIImage(data: data) {

   let photo:Data = image_download.sd_imageData(as: SDImageFormat.webP)!

}

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

add a comment |

Swift 4.0

pod both 'SDWebImage' AND 'SDWebImage/WebP'

import SDWebImage

if let image_download = UIImage(data: data) {

   let photo:Data = image_download.sd_imageData(as: SDImageFormat.webP)!

}

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

Swift 4.0

pod both 'SDWebImage' AND 'SDWebImage/WebP'

import SDWebImage

if let image_download = UIImage(data: data) {

   let photo:Data = image_download.sd_imageData(as: SDImageFormat.webP)!

}

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

edited Dec 30 '18 at 9:53

Ibrahim

3,38022036

answered Dec 18 '18 at 16:45

Dverdugo

2616

answered Dec 18 '18 at 16:45

Dverdugo

2616

answered Dec 18 '18 at 16:45

Dverdugo

2616

add a comment |

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