Recherche avancée

Sur d’autres sites (11199)

• Changes to the WebM Open Source License

  4 juin 2010, par noreply@blogger.com (John Luther)

  You’ll see on the WebM license page and in our source code repositories that we’ve made a small change to our open source license. There were a couple of issues that popped up after we released WebM at Google I/O a couple weeks ago, specifically around how the patent clause was written.

  As it was originally written, if a patent action was brought against Google, the patent license terminated. This provision itself is not unusual in an OSS license, and similar provisions exist in the 2nd Apache License and in version 3 of the GPL. The twist was that ours terminated "any" rights and not just rights to the patents, which made our license GPLv3 and GPLv2 incompatible. Also, in doing this, we effectively created a potentially new open source copyright license, something we are loath to do.

  Using patent language borrowed from both the Apache and GPLv3 patent clauses, in this new iteration of the patent clause we’ve decoupled patents from copyright, thus preserving the pure BSD nature of the copyright license. This means we are no longer creating a new open source copyright license, and the patent grant can exist on its own. Additionally, we have updated the patent grant language to make it clearer that the grant includes the right to modify the code and give it to others. (We’ve updated the licensing FAQ to reflect these changes as well.)

  We’ve also added a definition for the "this implementation" language, to make that more clear.

  Thanks for your patience as we worked through this, and we hope you like, enjoy and (most importantly) use WebM and join with us in creating more freedom online. We had a lot of help on these changes, so thanks to our friends in open source and free software who traded many emails, often at odd hours, with us.

  Chris DiBona is the Open Source Programs Manager at Google.

  

• Perspective transformations

  9 juin 2010, par Mikko Koppanen — Imagick, PHP stuff

  Finally (after a long break) I managed to force myself to update the PHP documentation and this time it was distortImage code example. Things have been hectic lately but that does not quite explain the 6 months(?) break between this and the previous post. As a matter of a fact there is no excuse for such a long silence so I will try to update this blog a bit more often from now on.

  Back in the day I used to blog the examples and update the documentation if I remembered but I am trying to fix this bad habit. Most of the latest examples have been updated in to the manual. In the case of the two last examples I updated the documentation first and then blogged on the subject.

  I took some time to actually understand the perspective transformations properly using the excellent ImageMagick examples (mainly created by Anthony Thyssen) as a reference. The basic idea of perspective distortion seems simple : to distort the control points to new locations. Grabbing the syntax for Imagick was easy, an array of control point pairs in the form of :

  php

  < view plain text >

  1. array(source_x, source_y, dest_x, dest_y ... )

  The following example uses the built-in checkerboard pattern to demonstrate perspective distortion :

  php

  < view plain text >

  1. < ?php
  2. /* Create new object */
  3. $im = new Imagick() ;
  4.  
  5. /* Create new checkerboard pattern */
  6. $im->newPseudoImage(100, 100, "pattern:checkerboard") ;
  7.  
  8. /* Set the image format to png */
  9. $im->setImageFormat(’png’) ;
  10.  
  11. /* Fill background area with transparent */
  12. $im->setImageVirtualPixelMethod(Imagick: :VIRTUALPIXELMETHOD_TRANSPARENT) ;
  13.  
  14. /* Activate matte */
  15. $im->setImageMatte(true) ;
  16.  
  17. /* Control points for the distortion */
  18. $controlPoints = array( 10, 10,
  19.             10, 5,
  20.  
  21.             10, $im->getImageHeight() - 20,
  22.             10, $im->getImageHeight() - 5,
  23.  
  24.             $im->getImageWidth() - 10, 10,
  25.             $im->getImageWidth() - 10, 20,
  26.  
  27.             $im->getImageWidth() - 10, $im->getImageHeight() - 10,
  28.             $im->getImageWidth() - 10, $im->getImageHeight() - 30) ;
  29.  
  30. /* Perform the distortion */ 
  31. $im->distortImage(Imagick: :DISTORTION_PERSPECTIVE, $controlPoints, true) ;
  32.  
  33. /* Ouput the image */ 
  34. header("Content-Type : image/png") ;
  35. echo $im ;
  36.  ?>

  Here is the source image :
  

  And the result :
  

• Creating buttons with Imagick

  9 juin 2010, par Mikko Koppanen — Imagick, PHP stuff

  A fellow called kakapo asked me to create a button with Imagick. He had an image of the button and a Photoshop tutorial but unfortunately the tutorial was in Chinese. My Chinese is a bit rusty so it will take a little longer to create that specific button

  The button in this example is created after this tutorial http://xeonfx.com/tutorials/easy-button-tutorial/ (yes, I googled “easy button tutorial”). The code and the button it creates are both very simple but the effect looks really nice.

  Here we go with the code :

  php

  < view plain text >

  1. < ?php
  2.  
  3. /* Create a new Imagick object */
  4. $im = new Imagick() ;
  5.  
  6. /* Create empty canvas */
  7. $im->newImage( 200, 200, "white", "png" ) ;
  8.  
  9. /* Create the object used to draw */
  10. $draw = new ImagickDraw() ;
  11.  
  12. /* Set the button color.
  13.   Changing this value changes the color of the button */
  14. $draw->setFillColor( "#4096EE" ) ;
  15.  
  16. /* Create the outer circle */
  17. $draw->circle( 50, 50, 70, 70 ) ;
  18.  
  19. /* Create the smaller circle on the button */
  20. $draw->setFillColor( "white" ) ;
  21.  
  22. /* Semi-opaque fill */
  23. $draw->setFillAlpha( 0.2 ) ;
  24.  
  25. /* Draw the circle */
  26. $draw->circle( 50, 50, 68, 68 ) ;
  27.  
  28. /* Set the font */
  29. $draw->setFont( "./test1.ttf" ) ;
  30.  
  31. /* This is the alpha value used to annotate */
  32. $draw->setFillAlpha( 0.17 ) ;
  33.  
  34. /* Draw a curve on the button with 17% opaque fill */
  35. $draw->bezier( array(
  36.           array( "x" => 10 , "y" => 25 ),
  37.           array( "x" => 39, "y" => 49 ),
  38.           array( "x" => 60, "y" => 55 ),
  39.           array( "x" => 75, "y" => 70 ),
  40.           array( "x" => 100, "y" => 70 ),
  41.           array( "x" => 100, "y" => 10 ),
  42.          ) ) ;
  43.  
  44. /* Render all pending operations on the image */       
  45. $im->drawImage( $draw ) ;
  46.  
  47. /* Set fill to fully opaque */
  48. $draw->setFillAlpha( 1 ) ;
  49.  
  50. /* Set the font size to 30 */
  51. $draw->setFontSize( 30 ) ;
  52.  
  53. /* The text on the */
  54. $draw->setFillColor( "white" ) ;
  55.  
  56. /* Annotate the text */
  57. $im->annotateImage( $draw, 38, 55, 0, "go" ) ;
  58.  
  59. /* Trim extra area out of the image */
  60. $im->trimImage( 0 ) ;
  61.  
  62. /* Output the image */
  63. header( "Content-Type : image/png" ) ;
  64. echo $im ;
  65.  
  66.  ?>

  And here is a few buttons I created by changing the fill color value :