How can I resize an image using Java

Question

I need to resize PNG  JPEG and GIF files  How can I do this using Java

User · Answer

It turns out that writing a performant scaler is not trivial. I did it once for an open source project: ImageScaler.

In principle 'java.awt.Image#getScaledInstance(int, int, int)' would do the job as well, but there is a nasty bug with this - refer to my link for details.

User · Answer

The Java API does not provide a standard scaling feature for images and downgrading image quality   Because of this I tried to use cvResize from JavaCV but it seems to cause problems   I found a good library for image scaling  simply add the dependency for  java-image-scaling  in your pom xml     lt dependency gt       lt groupId gt com mortennobel lt  groupId gt       lt artifactId gt java-image-scaling lt  artifactId gt       lt version gt 0 8 6 lt  version gt   lt  dependency gt    In the maven repository you will get the recent version for this   Ex  In your java program  ResampleOp resamOp   new ResampleOp 50  40   BufferedImage modifiedImage   resamOp filter originalBufferedImage  null

User · Answer

You don t need a library to do this   You can do it with Java itself   Chris Campbell has an excellent and detailed write-up on scaling images - see this article   Chet Haase and Romain Guy also have a detailed and very informative write-up of image scaling in their book  Filthy Rich Clients

User · Answer

Java Advanced Imaging is now open source  and provides the operations you need

User · Answer

After loading the image you can try   BufferedImage createResizedCopy Image originalImage               int scaledWidth  int scaledHeight               boolean preserveAlpha                System out println  resizing               int imageType   preserveAlpha   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB          BufferedImage scaledBI   new BufferedImage scaledWidth  scaledHeight  imageType           Graphics2D g   scaledBI createGraphics            if  preserveAlpha                g setComposite AlphaComposite Src                     g drawImage originalImage  0  0  scaledWidth  scaledHeight  null            g dispose            return scaledBI

User · Answer

The Java API does not provide a standard scaling feature for images and downgrading image quality   Because of this I tried to use cvResize from JavaCV but it seems to cause problems   I found a good library for image scaling  simply add the dependency for  java-image-scaling  in your pom xml     lt dependency gt       lt groupId gt com mortennobel lt  groupId gt       lt artifactId gt java-image-scaling lt  artifactId gt       lt version gt 0 8 6 lt  version gt   lt  dependency gt    In the maven repository you will get the recent version for this   Ex  In your java program  ResampleOp resamOp   new ResampleOp 50  40   BufferedImage modifiedImage   resamOp filter originalBufferedImage  null

User · Answer

Java Advanced Imaging is now open source  and provides the operations you need

User · Answer

You can use Marvin  pure Java image processing framework  for this kind of operation   http   marvinproject sourceforge net  Scale plug-in  http   marvinproject sourceforge net en plugins scale html

User · Answer

If  having imagemagick installed on your maschine is an option  I recommend im4java  It is a very thin abstraction layer upon the command line interface  but does its job very well

User · Answer

After loading the image you can try   BufferedImage createResizedCopy Image originalImage               int scaledWidth  int scaledHeight               boolean preserveAlpha                System out println  resizing               int imageType   preserveAlpha   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB          BufferedImage scaledBI   new BufferedImage scaledWidth  scaledHeight  imageType           Graphics2D g   scaledBI createGraphics            if  preserveAlpha                g setComposite AlphaComposite Src                     g drawImage originalImage  0  0  scaledWidth  scaledHeight  null            g dispose            return scaledBI

User · Answer

Java Advanced Imaging is now open source  and provides the operations you need

User · Answer

Simply use Burkhard s answer but add this line after creating the graphics       g setRenderingHint RenderingHints KEY INTERPOLATION  RenderingHints VALUE INTERPOLATION BILINEAR     You could also set the value to BICUBIC  it will produce a better quality image but is a more expensive operation  There are other rendering hints you can set but I have found that interpolation produces the most notable effect  Keep in mind if you want to zoom in in a lot  java code most likely will be very slow  I find larger images start to produce lag around 300  zoom even with all rendering hints set to optimize for speed over quality

User · Answer

Java Advanced Imaging is now open source  and provides the operations you need

User · Answer

Thumbnailator is an open-source image resizing library for Java with a fluent interface  distributed under the MIT license   I wrote this library because making high-quality thumbnails in Java can be surprisingly difficult  and the resulting code could be pretty messy  With Thumbnailator  it s possible to express fairly complicated tasks using a simple fluent API   A simple example  For a simple example  taking a image and resizing it to 100 x 100  preserving the aspect ratio of the original image   and saving it to an file can achieved in a single statement   Thumbnails of  path to image        size 100  100       toFile  path to thumbnail      An advanced example  Performing complex resizing tasks is simplified with Thumbnailator s fluent interface   Let s suppose we want to do the following    take the images in a directory and  resize them to 100 x 100  with the aspect ratio of the original image  save them all to JPEGs with quality settings of 0 85  where the file names are taken from the original with thumbnail  appended to the beginning   Translated to Thumbnailator  we d be able to perform the above with the following   Thumbnails of new File  path to directory   listFiles         size 100  100       outputFormat  JPEG        outputQuality 0 85       toFiles Rename PREFIX DOT THUMBNAIL     A note about image quality and speed  This library also uses the progressive bilinear scaling method highlighted in Filthy Rich Clients by Chet Haase and Romain Guy in order to generate high-quality thumbnails while ensuring acceptable runtime performance

User · Answer

Try this folowing method     ImageIcon icon   new ImageIcon  image png    Image img   icon getImage    Image newImg   img getScaledInstance 350  350  java evt Image SCALE SMOOTH   icon   new ImageIcon img   JOptionPane showMessageDialog null   image on The frame    Display Image   JOptionPane INFORMATION MESSAGE  icon

User · Answer

I have developed a solution with the freely available classes   AnimatedGifEncoder  GifDecoder  and LWZEncoder  available for handling GIF Animation  You can download the jgifcode jar and run the GifImageUtil class  Link   http   www jgifcode com

User · Answer

You could try to use GraphicsMagick Image Processing System with im4java as a comand-line interface for Java   There are a lot of advantages of GraphicsMagick  but one for all    GM is used to process billions of files at the world s largest photo sites  e g  Flickr and Etsy

User · Answer

If you dont want to import imgScalr like  Riyad Kalla answer above which i tested too works fine  you can do this  taken from Peter Walser answer  Peter Walser on another issue though               utility method to get an icon from the resources of this class         param name the name of the icon         return the icon  or null if the icon wasn t found              public Icon getIcon String name            Icon icon   null          URL url   null          ImageIcon imgicon   null          BufferedImage scaledImage   null          try               url   getClass   getResource name                icon   new ImageIcon url               if  icon    null                    System out println  Couldn t find     url                              BufferedImage bi   new BufferedImage                      icon getIconWidth                        icon getIconHeight                        BufferedImage TYPE INT RGB               Graphics g   bi createGraphics                   paint the Icon to the BufferedImage              icon paintIcon null  g  0 0               g dispose                 bi   resizeImage bi 30 30               scaledImage   bi    or replace with this line Scalr resize bi  30 30               imgicon   new ImageIcon scaledImage              catch  Exception e                System out println  Couldn t find     getClass   getName           name               e printStackTrace                      return imgicon          public static BufferedImage resizeImage  BufferedImage image  int areaWidth  int areaHeight            float scaleX    float  areaWidth   image getWidth            float scaleY    float  areaHeight   image getHeight            float scale   Math min scaleX  scaleY           int w   Math round image getWidth     scale           int h   Math round image getHeight     scale            int type   image getTransparency      Transparency OPAQUE   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB           boolean scaleDown   scale  lt  1           if  scaleDown                   multi-pass bilinear div 2             int currentW   image getWidth                int currentH   image getHeight                BufferedImage resized   image              while  currentW  gt  w    currentH  gt  h                    currentW   Math max w  currentW   2                   currentH   Math max h  currentH   2                    BufferedImage temp   new BufferedImage currentW  currentH  type                   Graphics2D g2   temp createGraphics                    g2 setRenderingHint RenderingHints KEY INTERPOLATION  RenderingHints VALUE INTERPOLATION BILINEAR                   g2 drawImage resized  0  0  currentW  currentH  null                   g2 dispose                    resized   temp                            return resized            else               Object hint   scale  gt  2   RenderingHints VALUE INTERPOLATION BICUBIC   RenderingHints VALUE INTERPOLATION BILINEAR               BufferedImage resized   new BufferedImage w  h  BufferedImage TYPE INT ARGB               Graphics2D g2   resized createGraphics                g2 setRenderingHint RenderingHints KEY INTERPOLATION  hint               g2 drawImage image  0  0  w  h  null               g2 dispose                return resized

User · Answer

After loading the image you can try   BufferedImage createResizedCopy Image originalImage               int scaledWidth  int scaledHeight               boolean preserveAlpha                System out println  resizing               int imageType   preserveAlpha   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB          BufferedImage scaledBI   new BufferedImage scaledWidth  scaledHeight  imageType           Graphics2D g   scaledBI createGraphics            if  preserveAlpha                g setComposite AlphaComposite Src                     g drawImage originalImage  0  0  scaledWidth  scaledHeight  null            g dispose            return scaledBI

User · Answer

Simply use Burkhard s answer but add this line after creating the graphics       g setRenderingHint RenderingHints KEY INTERPOLATION  RenderingHints VALUE INTERPOLATION BILINEAR     You could also set the value to BICUBIC  it will produce a better quality image but is a more expensive operation  There are other rendering hints you can set but I have found that interpolation produces the most notable effect  Keep in mind if you want to zoom in in a lot  java code most likely will be very slow  I find larger images start to produce lag around 300  zoom even with all rendering hints set to optimize for speed over quality

User · Answer

FWIW I just released  Apache 2  hosted on GitHub  a simple image-scaling library for Java called imgscalr  available on Maven central    The library implements a few different approaches to image-scaling  including Chris Campbell s incremental approach with a few minor enhancements  and will either pick the most optimal approach for you if you ask it to  or give you the fastest or best looking  if you ask for that    Usage is dead-simple  just a bunch of static methods  The simplest use-case is   BufferedImage scaledImage   Scalr resize myImage  200     All operations maintain the image s original proportions  so in this case you are asking imgscalr to resize your image within a bounds of 200 pixels wide and 200 pixels tall and by default it will automatically select the best-looking and fastest approach for that since it wasn t specified   I realize on the outset this looks like self-promotion  it is   but I spent my fair share of time googling this exact same subject and kept coming up with different results approaches thoughts suggestions and decided to sit down and write a simple implementation that would address that 80-85  use-cases where you have an image and probably want a thumbnail for it -- either as fast as possible or as good-looking as possible  for those that have tried  you ll notice doing a Graphics drawImage even with BICUBIC interpolation to a small enough image  it still looks like garbage

User · Answer

You can use Marvin  pure Java image processing framework  for this kind of operation   http   marvinproject sourceforge net  Scale plug-in  http   marvinproject sourceforge net en plugins scale html

User · Answer

You don t need a library to do this   You can do it with Java itself   Chris Campbell has an excellent and detailed write-up on scaling images - see this article   Chet Haase and Romain Guy also have a detailed and very informative write-up of image scaling in their book  Filthy Rich Clients

User · Answer

you can use following popular product  thumbnailator

User · Answer

you can use following popular product  thumbnailator

User · Answer

Thumbnailator is an open-source image resizing library for Java with a fluent interface  distributed under the MIT license   I wrote this library because making high-quality thumbnails in Java can be surprisingly difficult  and the resulting code could be pretty messy  With Thumbnailator  it s possible to express fairly complicated tasks using a simple fluent API   A simple example  For a simple example  taking a image and resizing it to 100 x 100  preserving the aspect ratio of the original image   and saving it to an file can achieved in a single statement   Thumbnails of  path to image        size 100  100       toFile  path to thumbnail      An advanced example  Performing complex resizing tasks is simplified with Thumbnailator s fluent interface   Let s suppose we want to do the following    take the images in a directory and  resize them to 100 x 100  with the aspect ratio of the original image  save them all to JPEGs with quality settings of 0 85  where the file names are taken from the original with thumbnail  appended to the beginning   Translated to Thumbnailator  we d be able to perform the above with the following   Thumbnails of new File  path to directory   listFiles         size 100  100       outputFormat  JPEG        outputQuality 0 85       toFiles Rename PREFIX DOT THUMBNAIL     A note about image quality and speed  This library also uses the progressive bilinear scaling method highlighted in Filthy Rich Clients by Chet Haase and Romain Guy in order to generate high-quality thumbnails while ensuring acceptable runtime performance

User · Answer

If you are dealing with large images or want a nice looking result it s not a trivial task in java  Simply doing it via a rescale op via Graphics2D will not create a high quality thumbnail  You can do it using JAI  but it requires more work than you would imagine to get something that looks good and JAI has a nasty habit of blowing our your JVM with OutOfMemory errors    I suggest using ImageMagick as an external executable if you can get away with it  Its simple to use and it does the job right so that you don t have to

User · Answer

After loading the image you can try   BufferedImage createResizedCopy Image originalImage               int scaledWidth  int scaledHeight               boolean preserveAlpha                System out println  resizing               int imageType   preserveAlpha   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB          BufferedImage scaledBI   new BufferedImage scaledWidth  scaledHeight  imageType           Graphics2D g   scaledBI createGraphics            if  preserveAlpha                g setComposite AlphaComposite Src                     g drawImage originalImage  0  0  scaledWidth  scaledHeight  null            g dispose            return scaledBI

User · Answer

If you dont want to import imgScalr like  Riyad Kalla answer above which i tested too works fine  you can do this  taken from Peter Walser answer  Peter Walser on another issue though               utility method to get an icon from the resources of this class         param name the name of the icon         return the icon  or null if the icon wasn t found              public Icon getIcon String name            Icon icon   null          URL url   null          ImageIcon imgicon   null          BufferedImage scaledImage   null          try               url   getClass   getResource name                icon   new ImageIcon url               if  icon    null                    System out println  Couldn t find     url                              BufferedImage bi   new BufferedImage                      icon getIconWidth                        icon getIconHeight                        BufferedImage TYPE INT RGB               Graphics g   bi createGraphics                   paint the Icon to the BufferedImage              icon paintIcon null  g  0 0               g dispose                 bi   resizeImage bi 30 30               scaledImage   bi    or replace with this line Scalr resize bi  30 30               imgicon   new ImageIcon scaledImage              catch  Exception e                System out println  Couldn t find     getClass   getName           name               e printStackTrace                      return imgicon          public static BufferedImage resizeImage  BufferedImage image  int areaWidth  int areaHeight            float scaleX    float  areaWidth   image getWidth            float scaleY    float  areaHeight   image getHeight            float scale   Math min scaleX  scaleY           int w   Math round image getWidth     scale           int h   Math round image getHeight     scale            int type   image getTransparency      Transparency OPAQUE   BufferedImage TYPE INT RGB   BufferedImage TYPE INT ARGB           boolean scaleDown   scale  lt  1           if  scaleDown                   multi-pass bilinear div 2             int currentW   image getWidth                int currentH   image getHeight                BufferedImage resized   image              while  currentW  gt  w    currentH  gt  h                    currentW   Math max w  currentW   2                   currentH   Math max h  currentH   2                    BufferedImage temp   new BufferedImage currentW  currentH  type                   Graphics2D g2   temp createGraphics                    g2 setRenderingHint RenderingHints KEY INTERPOLATION  RenderingHints VALUE INTERPOLATION BILINEAR                   g2 drawImage resized  0  0  currentW  currentH  null                   g2 dispose                    resized   temp                            return resized            else               Object hint   scale  gt  2   RenderingHints VALUE INTERPOLATION BICUBIC   RenderingHints VALUE INTERPOLATION BILINEAR               BufferedImage resized   new BufferedImage w  h  BufferedImage TYPE INT ARGB               Graphics2D g2   resized createGraphics                g2 setRenderingHint RenderingHints KEY INTERPOLATION  hint               g2 drawImage image  0  0  w  h  null               g2 dispose                return resized

User · Answer

Image Magick has been mentioned   There is a JNI front end project called JMagick   It s not a particularly stable project  and Image Magick itself has been known to change a lot and even break compatibility    That said  we ve had good experience using JMagick and a compatible version of Image Magick in a production environment to perform scaling at a high throughput  low latency rate   Speed was substantially better then with an all Java graphics library that we previously tried   http   www jmagick org index html

User · Answer

I have developed a solution with the freely available classes   AnimatedGifEncoder  GifDecoder  and LWZEncoder  available for handling GIF Animation  You can download the jgifcode jar and run the GifImageUtil class  Link   http   www jgifcode com

User · Answer

If  having imagemagick installed on your maschine is an option  I recommend im4java  It is a very thin abstraction layer upon the command line interface  but does its job very well

User · Answer

You could try to use GraphicsMagick Image Processing System with im4java as a comand-line interface for Java   There are a lot of advantages of GraphicsMagick  but one for all    GM is used to process billions of files at the world s largest photo sites  e g  Flickr and Etsy

User · Answer

Try this folowing method     ImageIcon icon   new ImageIcon  image png    Image img   icon getImage    Image newImg   img getScaledInstance 350  350  java evt Image SCALE SMOOTH   icon   new ImageIcon img   JOptionPane showMessageDialog null   image on The frame    Display Image   JOptionPane INFORMATION MESSAGE  icon

User · Answer

FWIW I just released  Apache 2  hosted on GitHub  a simple image-scaling library for Java called imgscalr  available on Maven central    The library implements a few different approaches to image-scaling  including Chris Campbell s incremental approach with a few minor enhancements  and will either pick the most optimal approach for you if you ask it to  or give you the fastest or best looking  if you ask for that    Usage is dead-simple  just a bunch of static methods  The simplest use-case is   BufferedImage scaledImage   Scalr resize myImage  200     All operations maintain the image s original proportions  so in this case you are asking imgscalr to resize your image within a bounds of 200 pixels wide and 200 pixels tall and by default it will automatically select the best-looking and fastest approach for that since it wasn t specified   I realize on the outset this looks like self-promotion  it is   but I spent my fair share of time googling this exact same subject and kept coming up with different results approaches thoughts suggestions and decided to sit down and write a simple implementation that would address that 80-85  use-cases where you have an image and probably want a thumbnail for it -- either as fast as possible or as good-looking as possible  for those that have tried  you ll notice doing a Graphics drawImage even with BICUBIC interpolation to a small enough image  it still looks like garbage

User · Answer

It turns out that writing a performant scaler is not trivial. I did it once for an open source project: ImageScaler.

In principle 'java.awt.Image#getScaledInstance(int, int, int)' would do the job as well, but there is a nasty bug with this - refer to my link for details.

User · Answer

Image Magick has been mentioned   There is a JNI front end project called JMagick   It s not a particularly stable project  and Image Magick itself has been known to change a lot and even break compatibility    That said  we ve had good experience using JMagick and a compatible version of Image Magick in a production environment to perform scaling at a high throughput  low latency rate   Speed was substantially better then with an all Java graphics library that we previously tried   http   www jmagick org index html

User · Answer

If you are dealing with large images or want a nice looking result it s not a trivial task in java  Simply doing it via a rescale op via Graphics2D will not create a high quality thumbnail  You can do it using JAI  but it requires more work than you would imagine to get something that looks good and JAI has a nasty habit of blowing our your JVM with OutOfMemory errors    I suggest using ImageMagick as an external executable if you can get away with it  Its simple to use and it does the job right so that you don t have to

[java] How can I resize an image using Java?

Examples related to java

Examples related to image

Examples related to resize