4 Replies Latest reply on Nov 27, 2012 8:46 AM by the_wine_snob

    Images added to the timeline lost their alpha-channel

    reinc-me

      Hi,

       

      I am using Premiere Elements 11.0 and added a few png-imags to the timeline (in a different channel than the imported movie). Every image had one part with completely opaque pixels and one part with completely transparent pixels. At first it showed up very nicely exactly the way I wanted it to. But when I added the fourth picture or so, all the transparent pixels in the images turned black.

       

      The source images still look exactly the same. I tried saving them again with Photoshop and with Paint.NET. I tried removing one picture and adding it again. I tried closing Premiere Elements and opening it again. Somehow nothing worked.

       

      I checked the 'Interpret Footage'-window and there is no check mark before 'Ignore Alpha Channel' for any of the images.

       

      I hope that someone here can help me ;-).

       

       

      Thanks,

       

      Gordian

        • 1. Re: Images added to the timeline lost their alpha-channel
          reinc-me Level 1

          I now tried to save these pictures as psd-files (they definitely still contain the transparency when I open them in Photoshop) and replacing the old images (the png ones) with the new ones (the psd-files). This did not help, too.

           

          However, I created a new image in Photoshop and just drew a black line on a transparent background. I imported this image as a psd-file into Premiere Elements in the same project and the transparency stayed!

           

          But I am still 100% sure, that the original images still have an area with an alpha value of 0.

           

          Maybe someone can get some sense from this - I do not. I will now create the original images again from scratch and hope, that they do not lose their transparency. Maybe someone has an idea, how I might have triggered this?

          • 2. Re: Images added to the timeline lost their alpha-channel
            the_wine_snob Level 9

            I create a lot of Images with Transparency, but always use PSD's. PNG's support Transparency, but the method differs from that in PSD. The only time that I have used a PNG with Transparency, has been a single logo, or similar.

             

            Why the first several PNG's workded, but then stopped working, is a mystery to me. Only thing that I can think of would be if the pixel x pixel size of those PNG's is large, then perhaps there is a resources issue, when enough are added to the Timeline. What are the pixel x pixel size of the PNG's?

             

            I also find it odd, that when a PSD w/ Transparency is added to the PNG's, it does not display its Transparency correctly, but if it IS a resources issue, that might explain it.

             

            I just looked back at a Project, where I used PS to create all of the Titles, including a very long Roll, and about a dozen more, and the PSD's w/ Transparency all worked perfectly. The Roll was 720 x 4000 pixels, but all the others were sized to the Project, 720 x 480 w/ PAR = 1.2. [In a PrPro Project, I had two such long Rolls, and ~ 50 Titles in PSD's w/ Transparency, with no issues, but that is a different program.]

             

            Maybe others have observed issues with Transparent PNG's, and can shed some light on things.

             

            In the meantime, it is good that you have the workaround of using PSD's w/ Transparency, to get your Project finished, but I am surprised at the behavior that your PNG's exhibited. A puzzle to me.

             

            Good luck,

             

            Hunt

            • 3. Re: Images added to the timeline lost their alpha-channel
              reinc-me Level 1

              Why the first several PNG's workded, but then stopped working, is a mystery to me. Only thing that I can think of would be if the pixel x pixel size of those PNG's is large, then perhaps there is a resources issue, when enough are added to the Timeline. What are the pixel x pixel size of the PNG's?

               

              The movie and all of the images had a resolution of 1920 x 1080. I am using Windows 7 Professional x64 with 8 GB RAM on an SSD. All of the project files were located on my (internal) HDD.

               

              In the meantime, it is good that you have the workaround of using PSD's w/ Transparency, to get your Project finished, but I am surprised at the behavior that your PNG's exhibited. A puzzle to me.

               

              This is what I did: I opened the png-files in Photoshop CS 6 and saved them again as psd-files. Then I used 'Replace Footage' in Premiere Elements to swap the png-files to the psd-files. This did not work, the in fact transparent pixels all became black.

               

              I wrote that I had success with a new psd-file - not with the images I actually wanted to use.

               

              I really do not know why, but I had to recreate the images from scratch again (luckily, that was not that difficult or time consuming). I saved them as png-files again (because I really do not see any reason why that should not work) and imported them. This time it worked as it was supposed to. But I can guarantee you that the new images had exactly the same pixel data as the old ones.

               

              I assume that this was some caching error. I did not tell one part of the story, because I thought that it was irrelevant. When I had five of my images working properly, I used a png compressor on the source files (I had a backup of them). It compressed them to one third of the original size - but also replaced the transparent pixels with white ones (must have used the wrong settings or so). Premiere Elements noticed the changed files and displayed them in the project now. I copied the backup files over the bad files and now the files reverted back to their initial state in Premiere Elements. The problem started when I added the next image to the project.

               

              I managed to finish the small project as intended, but I am still wondering about this strange thing. Thanks for your answer though. How do I mark this question as solved? Do I need to pick one 'correct answer' (but then I would not know which one to choose)?

               

              Message was edited by: reinc-me I corrected the formatting of one quote.

              • 4. Re: Images added to the timeline lost their alpha-channel
                the_wine_snob Level 9

                You can mark your last Reply as "Correct," as that is how you solved the issue. The thread will then show as "Answered," and that can be beneficial to others, if they encounter the same issue, and Search for the answers.

                 

                Good luck, and thank you for thinking about the marking of the thread. Too many never consider that, and it IS helpful for others.

                 

                Hunt