Can someone teach me the 2- pass encoding process ?

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • rash_rp
    Junior Member
    Junior Member
    • Mar 2002
    • 7

    Can someone teach me the 2- pass encoding process ?

    Hi !!!

    RASH here. Few days ago I posted a message as so which was the best codec between 3.x 4.x and 5 ? A lot of people told me that DivX 4 and 5 were better than 3.x if the encoding was done using 2-pass. Well...I have never used 2-pass.

    Can somebody be generous and tell me how all this 2-pass is done ( DETAIL INFORMATION ). I use XMPEG for encoding. Please tell me how all this is done. I'll be really greatful to anyone who does.

    Well....I was just wondering....if DivX5 is giving a good improvement in speed. I am getting a whooping 35 FPS on my P4 1.7 under XMPEG ( 1-pass ) w/ DivX audio.
  • Enchanter
    Old member
    • Feb 2002
    • 5417

    #2
    Basically, you do the first pass and make sure that either the .log (DivX4/5) or .stats (DivX3) file is already specified. The process is roughly as long as it takes to encode the whole movie, though it's generally faster than the second pass somehow.

    After the first pass has been done, you do the second pass. Make sure that no major settings have been changed (Deinterlace, crop & resize, smoothing, etc.) or else you will have to redo the first pass. Some may think that it's acceptable not to redo the first pass and in a way, it's a bit true. However, it remains a fact that optimum result won't be achieved that way, so keep that in mind.

    p.s. Have you actually bothered to read the guides instead? There are heaps of them!

    Comment

    • UncasMS
      Super Moderator
      • Nov 2001
      • 9047

      #3
      disagreed

      and btw i object to saying divx5/4 are better than 3!

      mpeg4 (ms v2 or divx3) with NANDUB is the most precise and reliable combo you could use for transcoding.

      Comment

      • Enchanter
        Old member
        • Feb 2002
        • 5417

        #4
        I agree very much with you, Uncas. However, the sheer number of people preferring DivX4/5, compared to 3, is so overwhelming here that if I were to object to everyone of them, I would end up sounding like a child. Probably they just don't know how to configure Nandub correctly...

        Comment

        • UncasMS
          Super Moderator
          • Nov 2001
          • 9047

          #5
          i know well enough what the quality looks like i get out of using NANDUB + MS V2.

          my impression is that ppl tend to use a new codec since they are not capable of handling the original well enough!

          if one is not willing to spend some time becoming familiar with decent tools, going for the the next hype that hits the ground is quite normal.

          Comment

          • Enchanter
            Old member
            • Feb 2002
            • 5417

            #6
            Perhaps a guide should be written for 2-pass encoding that goes like this. Beginners should use DivX4/5 and once they have gotten used to it, move to DivX3 which offers better quality. I like the sound of that.

            Comment

            • tcb121
              Junior Member
              Junior Member
              • Mar 2002
              • 12

              #7
              I disagree

              I had previously encoded 8 movies with the Divx 3.11 codec using low motion and fast motion codecs, and the results were not near as nice as the 2-pass mode with the Divx 4.12 method. I'll give you the colors come out a littler sharper with the 3.11 codec, but not enough to be concerned with. Plus, the filesize of the 2-pass 4.12 turns out to be smaller then with the 3.11 two pass method. Even Nickys pages show that the 4.12 codec with 2 pass look every bit as good if not better then the 3.11 two pass using highest quality you want.



              Its all in what you make of it. I'll stick to the 4.12 2-pass and reap the benifit of saving space and getting equal or better quality then the old 3.11 method. I know from encoding my own movies that using Flask or XMPEG with the 4.12 2-pass method that it is possible to make equal or superior quality movies vs the nandub 3.11 two pass method. Keep up the good work guys, and thanks for reading my two cents on this.

              Comment

              • UncasMS
                Super Moderator
                • Nov 2001
                • 9047

                #8
                nickys guides are quite good but way out of date when it comes to 2pass encoding!

                i had not spent hours on writing a decent nandub guide if i had been satisfied with an existing one (be it nickys or doom9's- i disagree with both)

                i can tell you nandub + ms v2 is much more precise than divx4 or 5.

                divx4 and 5 are blurry compared to divx3 or better the original ms v2 and the final output size with ms-v2/divx3 is MUCH better!!!

                but all in all i dont give a damn to what those guides try to tell me, i know what my results are.
                Last edited by UncasMS; 14 Mar 2002, 07:57 AM.

                Comment

                • Enchanter
                  Old member
                  • Feb 2002
                  • 5417

                  #9
                  tcb121

                  If you want to so chastise 3.11, then you should have done your comparison between 3.11 2-pass and 4.x 2-pass. Everyone knows that 2-pass mode is always more superior than 1-pass. I would of course prefer 4.12 2-pass to 3.11 1-pass when using Flask. However, I have done direct comparisons between Nandub results (3.11) and Virtualdub results (4.12). I always ended up discarding the resulting files of the latter method. It is noticably different as I previously mentioned.

                  Comment

                  • tcb121
                    Junior Member
                    Junior Member
                    • Mar 2002
                    • 12

                    #10
                    to Enchanter

                    I agree with you to a point, but I can argue either side. I have made two pass 3.11 with Nandub, but the file sizes to get the quality you must span over two CD's. I can also make a 2-pass with 4.12 at very high quality and span over two CD's, and the results look the same to me as the 3.11 2-pass with Nandub. I think both deliver GREAT quality and the 3.11 codec is a fine codec, and even better in some regards, but its like splitting hairs between the two. I have also done side by side comparisons with 4.12 and 3.11 and both look GREAT! I prefer the 4.12 with Flask because its more hands free. The only difference I see with the 3.11 codec is the colors come out slightly brighter, but thats it. Playback is the same, quality is the same. I'm not trying to down the 3.11 codec, but I don't think its worthy of significant praise over the 4.12. Most people will be more then content with the quality the 2-pass 4.12 with flask yields. I just don't see the grand difference that 3.11 has over 4.12. I would however like to know what it is that I'm missing? What does the 3.11 with 2-pass do to warrent such praise over the 4.12? Are the action scenes cleaner?, is playback smoother?, Is the filesize smaller then the 4.12 at EQUAL quality settings? Or are we just splitting hairs?

                    Comment

                    • UncasMS
                      Super Moderator
                      • Nov 2001
                      • 9047

                      #11
                      how close to you get to your desired final output filesize with divx4?

                      have you compared sharpness in both 2cd rips?

                      Comment

                      • Enchanter
                        Old member
                        • Feb 2002
                        • 5417

                        #12
                        As to why I prefer 3.11, it is of course a subjective matter. I have listed all the reasons above. Another reason is because Nandub offers more quality control than 4.x's bare configuration does. There is no beating the gauge settings, high/low-pass and many others.

                        I had a problem with 4.x once where a scene in an action part could not get enough bits and hence lots of macroblocks on particular areas. It does not matter that both the 3.11 and 4.x results had identical filesize. I could not find any settings with which I can tell the codec to assign more bits to that action scene (Such as the curve compression settings). Now, that's what I meant by quality control.

                        Comment

                        • tcb121
                          Junior Member
                          Junior Member
                          • Mar 2002
                          • 12

                          #13
                          I guess for the most part all of my movies have turned out GREAT, and I have had no reason to add more steps to the encoding process using Nandub. Just yesterday I encoded Mission Impossible 2 which has tons of action throughout. ( Car chases, things exploding, lots of high speed shooting etc ) The Movie is 123 minutes long and I wanted to Span it on to two CD's. From my experiance I don't even need to use a bitrate calculator, once you do so many you just kinda get a feel for the bitrate as I'm sure you guys do as well. I encoded it at 1300 and it turned out GREAT. The high speed scenes are awesome and play perfect, so I can't complain. To answer another question, I have looked at sharpness over my 2 CD rips with both methods, and like I have stated before, the only difference I see is that the 3.11 has ever so slightly better color. I'll give you a specific example. In the movie Topgun the pink sweater that Kelly McGillis has on in the bar scene is slightly more pink in the 3.11 rip than the 4.12 rip. However sharpness and playback quality are the same. I guess I'm looking for some specific examples of movies you guys have done and what your experiances have been. Making Divx movies are trial and error sometimes, and I'm sure you guys have played around with different settings and have had better success with some then others. My point that I am trying to make is that 4.12 using flask yields favorable results to any other method out there and that even the mighty 3.11 with Nandub and MS V2 only yield a minor difference in quality. Everyone can have their own oppionion, but these are my findings. What types of movies are you encoding?? Are they PAL vs NTSC or what? All of my movies to date are NTCS progressive, so using my method my be more suited to an american point of view. Maybe Nandub yields a significant difference with a PAL movie or interlaced movies, but I just don't see any real difference with the NTSC progressive ones that I have encoded. Thanks for your replys back. I'll have to look more into Nandub in the future when I have more time to tinker with the settings some more. For now, Flask is an easy way for me to backup my movies and its a solution that delivers GREAT results for me. Keep up the GREAT posts on this fourm, UncasMS and Enchanter, you guys are very helpful from what I have read of your posts, and I know that everyone has learned a great deal from the two of you.

                          Comment

                          • Enchanter
                            Old member
                            • Feb 2002
                            • 5417

                            #14
                            Glad for the compliments. Hope that you would one day join us in the Nandub wagon though.

                            Comment

                            • gerbilhamster
                              Junior Member
                              Junior Member
                              • Mar 2002
                              • 9

                              #15
                              I'm also trying to do two pass but I don't know how to create the divx.log to enable me to do a second pass - I'm using DivX5.0 Pro.

                              Please help.

                              Comment

                              Working...