batch convert png's to jpeg's

Discussion in 'Mac Basics and Help' started by mark2288, Apr 11, 2008.

  1. mark2288 macrumors regular

    Jan 11, 2006
    I have a bunch of pngs that I'd like to convert to jpeg's as easily as possible. I have Adobe CS3 if that app is capable of doing it.

  2. Latro macrumors member

    Mar 23, 2008

    Do you have Pixelmator? If not, you should. Then you can use automator with these steps:

    1. Find Finder Items - Do a search to select all the .png images you want to transfer to jpeg
    2. Get Selected Finder Items
    3. Copy Finder Items - This will make sure you keep an original copy of all your .png images should anything go wrong.
    4. Change Type of Images (This step Requires Pixelmator - I believe there is a free trial you can download but it is well worth the $).

    Run the automator process and all your pictures are converted. I just tried this out and it converted about 40 png files to jpeg in 3 seconds.

    For more hints and tips. Head over to!
  3. richard.mac macrumors 603


    Feb 2, 2007
    51.50024, -0.12662
    ^ yep i was just about to suggest that! Automator is great for these things. Automator will ask you if you would like to add a "Copy Finder items" action after you add the "Change type of images" action so you dont have to add it. when you have the workflow setup in Automator just press the play button if you only plan on using it once and not saving it.

    also Latro you dont need Pixelmator for the change type of images action. it uses Preview.
  4. mark2288 thread starter macrumors regular

    Jan 11, 2006
    thanks for the help. i went ahead and used Latros' flow but used Preview instead since i hate installing new things! thanks again!
  5. BarnCat macrumors newbie

    Jun 27, 2008
    In the western mountains.
    Ready to pull hair out

    Okay - I am so glad I found you guys. I am using iphoto for image storage/organization. But I edit in photoshop, using a nice little array of actions and tricks. I really dislike jpegs, and would love to store everything as png. After reading this and some other things, I put together a little workflow that downloads from the camera, changes to PNG, imports into iphoto. Worked like a charm except for two things: A) all of the camera meta data was lost, and I end up with only the date and time of my download. B) when things are done this way, iphoto does recognize duplicates. I guess that should be obvious, since all the stuff in iPhoto is .jpeg, so the names are not the same (duh, me).

    But what about the meta data? Do any of you know why this would happen? PNG can carry textual meta data. I'd ask my kid, Mr. Hey-let's-write-a-script-for-that, but he's gone to Argentina for two years. So I'm looking for a mensch who can teach me a thing or two.
  6. MarcusSparkus macrumors newbie

    Dec 20, 2008
    png or gif to jpeg?? Why are you making it so freaking complicated??

    Don't listen to them and don't spend a penny you already spent a ton of dough on the best operating system on the planet. Open it with Preview, file, save as jpeg or whatever format you want, duh.
  7. GGJstudios macrumors Westmere


    May 16, 2008
    First, you just responded to a thread that's more than a year old.

    Second, it would help if you took the time to read the thread title and the OP's post. They're looking for a batch conversion for a bunch of pics. Doing them one by one is extremely inefficient.
  8. plinden macrumors 68040


    Apr 8, 2004
    Wow - old thread.

    For those who come to this later, open Terminal, cd to the directory containing your JPGs and type:
    mkdir pngs; sips -s format png *.* --out pngs
  9. quantum003 macrumors 6502a


    Apr 27, 2009
    If you have Adobe Photoshop CS3 you can choose "Automate" --> Web Photo Gallery... it will take a folder full of PNGs or any other image file and dump a bunch of resized jpegs into a new folder for you.
  10. jazzkids macrumors member

    Feb 3, 2004
    Providence, RI
  11. rrandyy macrumors 6502

    Jan 14, 2009
    I realize this is an old thread, but I found it very useful and want to update it for others who search for it. If you want to convert png images to jpeg, you should use the following:

    mkdir jpegs; sips -s format jpeg *.* --out jpgs
    If the png images were generated using screen capture, you can set the default osx screen capture format to jpeg, rather than png using this command:

    defaults write type jpg
    Then restart your computer for the change to take effect. To revert back to the default png format, use "defaults write type png".

  12. matrix07 macrumors 601


    Jun 24, 2010
    Sorry to revive old thread but this is such a good tip. The problem though is it doesn't help newbie (like me) much so I recap it a bit.
    1. Open Automator. Select Application and choose.
    Now you choose the task from the left pane and drag it to action pane.
    2. drag Get Specified Finder Items. Drag and drop all your files you want to convert.
    3. drag Copy Finder Items. Create another folder for the converted pictures to go to.
    4. drag Change Type of Images (Preview, you don't need Pixelmator) change format to JPEG, then Run.
    5. Have a nice sip of beer and.. voila!
  13. henryseiden macrumors member


    Aug 24, 2009
    batch convert files in a hierarchy from png to jpg

    The only things I would have to add is that (in my case at least, where I am converting many files in a specific folder heirarchy) I manually copy the entire grouping to a flash drive and convert all the files copied on the Flash drive with the Automator step Copy Finder items. I suppose that the Copy step could be used but why?

    Also note that when Finding the items the select by extension method doesn't work for me. I had to use by name, ends with...

    I found this much easier to make as a template and/or run on a one time basis that dealing with Terminal. This could also be done there though.
  14. nicolanicola macrumors member

    Jan 11, 2009
    I'm trying to do this. I have many files in different folders that I want to be changed to jpgs. They all have the same name so I can't save them in one folder, I want them to be saved in their source folder i.e. where they came from. How is the best way to do this? Thanks guys.
  15. c00lryguy macrumors newbie

    Apr 7, 2012
    Here's what I did:

    1. Open Automator.
    2. Create a new "Service".
    3. To the right of "Services receives selected", select "images files" in the drop-down.
    4. Select "Finder" in the drop-down to the right of the previous drop-down.
    5. Search for "Change Type" in the search bar.
    6. Add the action provided by Pixelmator. I have not tried the action provided by Preview, although I'm sure it works the same. You may be prompted to add a task to copy the image, but Pixelmator's action already does this, so select "Don't Add" if asked.
    7. Change "To Type:" to "PNG" in the action's settings.
    8. Save the service as "Convert to PNG".

    Now, when I select some JPG files in Finder and right click, I see will see my entry in my context menu. =D
  16. matrix07 macrumors 601


    Jun 24, 2010
    I think the best way is to skip step 3 on my guide.
  17. jazbek macrumors newbie

    Nov 1, 2010
    This should be

    mkdir jpegs; sips -s format jpeg *.* --out jpegs

Share This Page