Announcement

Collapse
No announcement yet.

my SVCD test

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • my SVCD test

    I just tested a couple DVD players with a SVCD that I burned on CD-R. Here are the specs:

    Original video was from Sony D8 camcorder, 'captured' via Canopus Raptor.

    Encoded with bbMPEG using SVCD profile. Adjusted some advanced settings to use fields, specifically the lower field. CBR was 2600 I think, whatever the default setting was. Then used I-author to multiplex and author the SVCD. The content consists of one menu screen and the video. Burned using Adaptec EasyCD Creator 4.

    Now for the results, courtesy DVD floor units at Circuit City. The first one was the Apex600a. When I put the CD in, it was recognized and "SVCD" appeared on the screen. I pressed Play once and the menu screen came up, looking GREAT. (ASIDE: I created a snazzy menu screen at 720x480, and then resized to 480x480. It looks in correct proportions on the TV screen.) I hit Play again and the video began. It filled the screen but had HORRIBLE artifacts.

    Next I put the CD in a Pioneer 525. At first I hastily pushed Play and the menu screen came up looking squished to the left side of the screen. Pushing Play again started the video. No artifacts this time, BUT the screen consisted of two parts. On the left was a large square (squished) block of video, and on the right was a vertical rectangle (very squished) of the same video.

    I ejected the CD and reloaded it. This time I waited until it read the CD, and "VCD" appeared on the screen. Now the menu appeared in the correct proportions. Sadly the video still had the improper formatting. No artifacts though.

    Conclusion: I am wondering if the Apex can handle the bitrate. As for the Pioneer, it may be reading the CD as a VCD, and this may be I-author's fault. I-author incorrectly puts the MPEG-2 tracks in a VCD directory name ('mpegav') instead of the correct directory name for SVCD, which is 'MPEG2'. (This is also apparently why PowerDVD won't play I-author SVCDs.) I'm hoping to find a simple way of renaming that directory prior to burning a CD, and seeing the results. I also am looking for a software DVD player that will play I-author SVCDs.

    Any comments or suggestions would be appreciated!!

  • #2
    BrianP: The Apex is fairly notorious for showing off compression artifacts. (though properly adjusting it's output by using Video Essentials or something like that is supposed to take care of that problem) 2.6 Mbit/sec isn't that high, and the Apex can certainly handle it. (DVD bitrates are usually in excess of 5 Mbit/sec) If by artifacts you mean the image you get is fairly blocky, you can adjust that in bbMPEG by increasing the motion prediction by going into Advanced Vidoe Settings, going into the Motion Estimation menu, and increasing the horizontal and vertical Pel Movement settings. (at least to 9)
    The real problem is that bbMPEG encodes at constant bitrates. If there were a way around that, I would be ready to call it the superior encoder.

    Comment


    • #3
      Walrus: Actually for the purpose of this test I *think* I did set the horizontal and vertical Pel settings to 9.

      I say "I think" because I did a few test encodes when I was trying to get I-author to cooperate with creating a CD image and I did the process more than once. (I ended up finding a specific version of I-author that worked...the 2.6MB version out there WORKS, the 3.3MB HAS PROBLEMS). On some tests I adjusted the Pel settings, some I didn't. But I'm pretty sure I did it for this one.

      In any case the Apex showed big blocks, and lots of them. It looked like 10th generation VHS it was so bad. I think it went beyond mere compression artifacts. But the Pioneer had no such problem.

      I would like to do another test with a mix of simple and complex scenes. For this test I purposely chose a complex waterfall sequence to see how a worst-case scenario might look.

      Comment


      • #4
        BrianP: For I-Author to put MPEG-2 tracks in MPEG-2 folder, go to View -> Preference -> Project Preference and switch title mode to "Super VCD".

        Thanks...

        DGCom
        DGCom

        Comment


        • #5
          DGCom: Thanks for the tip! That did put the mpeg-2 file in the correctly named folder. PowerDVD still won't read the disk though. Perhaps this is a stupid question, but do I need a DVD drive to read a SVCD? My impression was that I could use a normal CD drive to read the CD-R and play SVCDs.

          Comment


          • #6
            You should be able to use normal CD-ROM. Why not?

            WinDVD is supposed to be able to play SVCD...

            I'm just started playing with SVCD.
            Brian, when you burn cif image with EZCD (what version?) does it report any errors?

            DGCom
            DGCom

            Comment


            • #7
              DGCom: I used EasyCD Creator 4. You just select the disk image and burn the CD. No errors.

              The directory contents of the SVCD are:
              --Autorun (nothing in this folder, but I think you can set it up in i-author to autorun stuff)
              --Data > svcddata (empty)
              --Ext (contains the file scandata.dat)
              --mpeg2 (contains the file avseq01.mpg)
              --Segment (contains the files Item001.mpg and Item002.mpg ... these are the menu screens)
              --svcd (contains the following: entries.svd, info.svd, lot.svd, pds.svd, search.dat, spicontx.svd, tracks.svd)
              --Vmp > svcdj (empty)

              Comment


              • #8
                I'm using EZCD 4.02 in w2k and it tells me that "there is not enough data" (or thomething like that) after burning image...
                The error comes from CDRW (Yamaha), not from EZCD... Disk is readable an I can "play" mpg file from it using WinDVD - but it strange - audio is fine, but video is slow and unsync.
                Anyway, my Pioneer DV-414 do not recognize those disks at all, so, I'll probably postpone my attempts to make SVCD...

                DGCom
                DGCom

                Comment


                • #9
                  When I play the SVCD mpeg file in WinDVD it is completely out of sync with the audio. The video plays one second--and pauses--and plays one second--and pauses--and so on. Audio continues uninterrupted. I thought it might be something with my CD drive but copying the mpeg file to the hard drive didn't change anything.

                  I don't recall this occurring when I tested the SVCD on the Apex and Pioneer players. Any idea what's going on?

                  Comment


                  • #10
                    Hm... Exactly my symptoms...
                    Either of:
                    • I-Author do not produce correct SVCD
                    • All those players are not compatable with SVCD


                    I'll try the following (whenever I'll get some spare time):
                    • Try another software SVCD player
                    • Use Philips tools (and SVCD verifier)


                    Also, I'll try to order SVCD disk from Philips...

                    By the way. SVCD assumes VBR encoding in MPEG-2. So, there may be a problem that bbMPEG standalone makes CBR only right now... Probably, next version (and the last one ) will include VBR support. The only way to make correct VBR (field-encoded) right now is to use MainActor 3.51 - it includes this latest "bbMPEG" functionality...

                    DGCom
                    DGCom

                    Comment


                    • #11
                      I received a reply from the bbMPEG author in another forum. He said he thinks the problem with the video getting squished is due to the sequence display extensions that are put into the video stream by bbMPEG. Also:

                      "If you would want to try a pre-release of version 1.2 which has an option to turn off the sequence display extensions (and they are off by default for SVCD), try downloading http://members.home.net/beyeler/pre12.zip.

                      "This version also implements a simple variable bitrate mode but it is uncapped, meaning the bitrate will be whatever it will be, there is no way to limit it so it never goes above a maximum value. This may or may not work for SVCD if the bitrate goes above 2.6mbps. Also, note any previous PAR files will not work with this version."

                      He also says the actual release of v1.2 should be done this week.

                      [This message has been edited by BrianP (edited 10 April 2000).]

                      [This message has been edited by BrianP (edited 12 April 2000).]

                      Comment


                      • #12
                        It is crushing on my files... I was going to send an email to Brent anyway...

                        And I also monitor DVD Soft forum...

                        By the way, after looking at the prices for test SVCD disks, I decided not to buy... $115 for one including shipping... No way!

                        DGCom

                        P.S. I was able to run new bbmpeg.dll with older version of avi2mpg. So, I'll try to make another SVCD tonight...


                        [This message has been edited by dgcom (edited 10 April 2000).]
                        DGCom

                        Comment


                        • #13
                          dgcom:
                          What do you mean by the LAST one????
                          BrianP:
                          Thank you for posting the link! VERY cool stuff indeed.. (bbMPEG is getting very close to the perfect MPEG encoder now)

                          Comment


                          • #14
                            Walrus: Unfortunately, Brent Beyeler is going to drop making free version... He will dedicate his effort on making MPEG plugin for MainConcept MainActor...

                            But I think, if evry bbMPEG-lover will send him a note... I did it already. I think, he can make "previous" (from current in MA) version available for free (or shareware).
                            Unless he is tighten with some kind of contract with MainConcept...

                            Even then, I'll continue to use MA instead...

                            DGCom
                            DGCom

                            Comment


                            • #15
                              dgcom:
                              Well I'm definitely sorry to hear that news (from a selfish perspective) I'm glad for Mr. Beyler that he has been able to gain from his effort as he deserves to.
                              I just dug through the source code of beta 18, and as there does not appear to be any licensing information on the source code, I am a little uncertain as to whether or not others can continue his work on the free version.. (for instance, I am toying around with an idea to try to make a VFW interface so it can be used as a standard AVI codec, or trying to code an interface directly into Virtualdub)
                              Actually, if there is no copyright info in theory anyone can take custody of the code, but that would be a pretty scummy thing to do, and it would be better to have the author's blessing.
                              I guess I should email him. (I don't know if I have the time, and it's questionable if I have the expertise to work on it, but it's worth a shot)

                              [This message has been edited by Walrus (edited 12 April 2000).]

                              Comment

                              Working...
                              X