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    h.264 quality testing

    This threads purpose is to be the place where I will be posting links to test files for encoding quality in the run up to our new formats and encoding practices. The intention is to fine tune what we are doing so as many members benefite from the changes as possible.

    The first file is here:http://abbywinters.com/newsletter/ne...64-1mb-720.mp4

    We are interested in how you think it compares to the normal formats you can download this newsletter in and how it compares in download time (and ultimately file size)

    Please post your comments and crits. As well as your suggestions!
    There will be more files to come in the comming weeks

    #2
    I assume that the WMV version of this same newsletter will be up soon on the main page, so that we can compare apples to apples.

    Download time for me was about 1:45. My download speed is about 310 KB/s.

    At about 1:07, in the Carey and Skye clip, there were some artifacts around the head and upper body of the dark-haired model.

    From 1:45 to 1:50, I was impressed with how the skin tones didn't get too blocky.

    From 2:19 to 2:29, there was more movement and I noticed some blocks in skin areas.

    That's what stood out in one viewing, anyway. It was very good, overall. My system: Mac Intel Core Duo 2GHz, 1400 X 1050 video, Planar PE2010 flat-panel monitor. I viewed full-screen but also switched back to actual size to compare some portions.

    Comment


      #3
      OK, the WMV version just became available, so now I can compare them. I'm using Quicktime with Flip4Mac.

      1. I don't know if you're interested in this right now, but the sound level in the h.264 file is lower than the WMV version.

      2. I froze both versions at 0:04 and noticed that there was less detail in skin in the h.264 version.

      3. At 1:07 in the WMV, it looks a little better, but the difference isn't as great as I was expecting, now that I can see both versions together.

      4. At 1:47, once again I can see more detail in skin areas in the WMV. The difference is most apparent on the left side of the screen.

      5. At 2:19 to 2:29 in the WMV, the quality is better. I was focusing on the model's upper legs.

      I hope that helps.

      Comment


        #4
        Are both the wmv and h264 overly bright (whiteness, overexposed how do you call it?) or is that just me ?

        Comment


          #5
          Looks great for the most part.
          I did notice some blocking at about 1:45 (the hand on the left side of the screen)
          Also, at about 3:43 there is a small glitch (almost looks like a dropped keyframe), and continues happening a few times after that.

          [edit]
          Oh, I should probably mention that I'm using VLC 0.9.0 (svn build) on Linux.

          Comment


            #6
            The 2 video newsletters I've seen in MP4 are not good in my opinion so far. The flesh tones are way off somehow. They are too orange or white (overexposed). Too much contrast and too few flesh tones. Also the quick movement at 5 sec with the hands are very bad.

            Comment


              #7
              It works here, but the parts with movement are pixeled at times. Quality could be better, but it does work without glitches orso.

              Comment


                #8
                (Mac OS 10.4.11)

                Tried it several times in QuickTime Player. The good news is that the previous issue with the wrong aspect ratio is gone. The bad news is that the player consistently froze or crashed after a couple of seconds.

                Playback in VLC worked fine.

                Comment


                  #9
                  I'm certainly no computer expert and don't have an understanding of a lot of the computer jargon being written in these threads but I' II give my 2 cents for what it's worth. Unlike the file I downloaded in the original thread the file this time didn't work properly in either QT or VLC and didn't work at all with WMP. But once again when I changed the file extension to .mpg or .avi it worked perfectly with WMP.

                  According to some this shouldn't work, but for me it is, why is it so?

                  STOP PRESS!- before I posted this reply i decided to analyze the file with codec installer using the original file extension of .mp4. It told me it was a corrupted file and supplied the following breakdown of the codecs in the file for those of you who know about these things!

                  .mp4:mpeg-4 video (54.8%)
                  .3G2:3GPP2 multimedia audio/video (38%)
                  .Mov:quick time movie (3.9%)
                  .mp4:generic mp4 container(2.3%)

                  Comment


                    #10
                    Weird, you are all using the newsletter_080218-h264-1mb-720.mp4 file right? Which is about 34Mb in size?

                    Doc. what do you mean precisely by 'did not work in WMP', did it not open or did it refuse to play? Try left-clicking the file when it has it's original name and extension and then select 'open with.. Windows Media Player'. You are correct in saying that only a change of extension should not make a file play or not play.

                    Comment


                      #11
                      Originally posted by Frans View Post
                      Weird, you are all using the newsletter_080218-h264-1mb-720.mp4 file right? Which is about 34Mb in size?

                      Doc. what do you mean precisely by 'did not work in WMP', did it not open or did it refuse to play? Try left-clicking the file when it has it's original name and extension and then select 'open with.. Windows Media Player'. You are correct in saying that only a change of extension should not make a file play or not play.
                      Yes I am talking about the above mentioned file. If i try to play it in it's original file extension i get the standard WMP error message of WMP encountered a problem whilst trying to play the file with the choice of close or web help. If I change the extension to .avi or .mpg it will play fine with WMP , however if you check the properties of the file theres no information in the "video" section which is strange as this usually means in my experience the file wont play at all. I have imported the file when in .avi and .mpeg extension into windows dvd/movie maker and it was accepted by both and i can play the file in WMM.

                      I am using vista home premium.

                      Comment

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