5 Replies Latest reply on Jun 21, 2011 9:55 AM by Ted Smith

    How can I cut up a video file into smaller bits?

    Ted Smith Level 3

      I shot around 3 hrs of 1920x1080 AVCHD in 2 clips (a wide shot of the stage of a musical production I performed in) It all fits in the internal memory of my camera.

       

      Two friends shot medium and closeups in Standard AVI with a view of making a DVD (2 disks)

       

      They will be editing it in Premier Pro standard def.(a 3 camera production!)

       

      When I convert my AVCHD to AVI SD, each of my 2 reduced clips is still too big to fit on one dvd disk as a data disk.

       

      How can I cut each clip in half to fit on a total of 4 disks so I can send them the video?

       

      If I make two AVCHD projects out of each clip in PE9 and share as DV, the quality is badly degraded. Near vertical lines become very jagged and the picture is much softer than if it had been originally shot in SD.

       

      If I make a PE9 DV project and import the AVCHD instead, I get the red line and the picture once rendered is no better.

       

      I have seen references to a lossless codec. Would this do the job in PE9 and how do I implement it?

       

      The 4Media converter does a much better job of converting to SD but how can I cut the new file in half?

        • 1. Re: How can I cut up a video file into smaller bits?
          the_wine_snob Level 9

          For the transport of the material from your machine to the one with PrPro, I would pick up an inexpensive external HDD. As this will just be a transport device, a USB 2.0 connection should be just fine. I would Export/Share to an internal HDD, and just Copy the files to the external.

           

          As for HD to SD, getting the ultimate results is not the easiest thing. This HD to SD TUTORIAL has about the best workflow, that I have seen. It relies on open source programs. There is probably mention of PrPro, but as Premiere figures in sparingly in the down-rezzing process, then PrE will do all that you need. Personally, I find the down-rezzing in either PrE, or PrPro to be less than ideal.

           

          One thing that needs to be pointed out, regarding critiquing the HD to SD footage is that if you are viewing on a high-rez computer monitor, or an HD TV, the output files will never look nearly as good, as your original material, as the SD material is going to be but 720 x 480 for NTSC, or 720 x 576 (PAL). The best way to judge quality is to view the output files on a calibrated NTSC (or PAL) CRT monitor. That is as good as it gets.

           

          Good luck,

           

          Hunt

          • 2. Re: How can I cut up a video file into smaller bits?
            the_wine_snob Level 9

            As far as the lossless CODEC's go, the results are very slightly better, than going with DV-AVI Type II's, but not THAT much better, and the file sizes will still be quite large. The two most often used (at least around my studio and in those of my friends) are Lagarith Lossless, and UT.

             

            If the external HDD, mentioned above, is not viable, then you could cut your Timeline into about 8 pieces of 15 mins. each, based on a 2 hour production, and then do DVD-Data with DVD-5's, or cut into about 4 pieces, if you go with a DVD-9 (DL).

             

            Personally, with the prices of the externals being so low, that would be my method. I Fed-X those around the country, and have never had an issue.

             

            Now, one question probably needs to be addressed: are you and the other editors on PC's? The reason that I ask is that an external that needs to go from Mac to PC, or the other direction, will have to be formatted as FAT-32, and that imposes a 4GB file size limit (back to cutting the Timeline), but if you are both on PC's, just check the format of the new external, and if FAT-32 (often the state from most mfgrs.), just Convert to NTSF, and you will have no file size issues.

             

            Good luck,

             

            Hunt

            • 3. Re: How can I cut up a video file into smaller bits?
              Ted Smith Level 3

              I would point out that Standard Def here in Australia(576) is 12% better vertical resolution that in USA(480).

              So European & Aussie SD doesnt look quite so bad compared with full HD

              In fact if you stand more than 4 metres from a 40" screen, most people cant see the difference between good SD and full HD.because the eye cant resolve such fine detail at that dustance even with perfect vision.

              This is providing the original material was shot with a good camera capable of HD and it was downscaled properly.

               

              Converters

              I. downloaded trials of the following converters and rank them in the following order

              1. 4Media version 6 AVCHD to AVI converter ($37)

              2. Prism

              3. AVS

              4. Wondershare

              5. PE9 making seperate SD projects

               

              I found them obviously different with PE9 right at the bottom of the scale! I will never use it again to make a SD project.

              Blurryness and jagged or twinkling diagonal lines were the most common faults.

               

              4Media shone above all the others. When used on the highest bit rate was only slightly softer than the ACVHD material with no jagged diagonal lines but it produced an AVI file the same size as the AVCHD.

              When I set the bit rate so the AVI file produced was half the original AVCHD, the quality was equal to original SD video Shot on my old Sony Camera that cost me $2000 5 years ago.

              I can split the files with this program too!

               

              Judging picture quality

              All pictures will have errors and be less than ideal. It's just a matter of how many are acceptable.

              The ONLY way to evaluate how good a picture is to view it on the best  possible setup. You can't judge vertical resolution on an old CRT TV  which is a different number of lines anyway (525 or 625) so evaluation  is impossible. Digital TV thru a set top box to a CRT TV is far worse  than the original analog.

               

              Because everyone knows SD is worse then HD but it should only be half as bad (576 is about half of 1080)

               

              Because I wear glasses that perfectly correct my focus and slight astigmatism, I have a good rough method of calibrating my eyes so I can relatively judge quality of different pictures on different systems.

              I vary the difference between myself and the screen so the left and right edges are in line with my fingers inside the frames of my glasses!

              This is equivalent to  sitting two thirds from the screen in the average picture theatre where  you can comfortably sit without being disturbed by deficiencies of  most film and HD projection.

               

              Applying this to my computer screen I can now judge pretty well. If a picture looks really good under these circumstamces it IS good and I can easily see any meaningfull errors.

               

              Using my calibration "method", I found that full HD on my 40" LCD is noticeably sharper than the best cinema in our city (we have 39 of them, some with 8 theaters ) and after enquiries found they are all 1440x768 and not true HD at all.If you get there earlier than when they boot up their projector you can often see this in their boot up screen.

              Worse still they slightly defocus them so you can see the pixel structure close up!

              The now rare 35mm Film projection ranks even lower by the time copies are distributed.

               

              You can't buy analog TVs or CRT screens anymore here anyway and Analog TV finishes here completely next year.

              • 4. Re: How can I cut up a video file into smaller bits?
                the_wine_snob Level 9

                Ted,

                 

                This is the type of monitor that I was referring to: http://www.bhphotovideo.com/c/product/646464-REG/Ikegami_TM15_70R_15_TM15_70R_CRT_Color.ht ml

                 

                With DVD giving way to BD, and SD in general being replaced by HD almost everywhere, it will be moot soon.

                 

                At some point in time, we will not have to be concerned with non-square pixels (HD Anamorphic will probably go away too), and everything will be PAR = 1.0.

                 

                However, until that happens, we'll still have to deal with technology from the 1990's. It was designed for a different time, and is still viable, but to compare HD material to SD leads many to believe that the editing program is somehow corrupting their material, when going to DVD. In most cases, if things were done properly, it is not - the lack of quality is inherent in the SD material, designed to display on a CRT TV, at either 720 x 480, or 720 x 586.

                 

                Now one thing that impresses me is seeing my DVD's displayed on one of my HD TV's, played through one of my up-rezzing BD players. Wow, the chips in those players really does a sweet job, and the DVD's have never looked so good - not full BD HD, but much better than with the old DVD players and my CRT TV's.

                 

                Now what I do not understand is the common desire to shoot HD, but then to resist outputting to BD. I think that many are under the impression that if they author to DVD, the program will magically compress those 1920 x 1080 Frames down to 720 x 480 to fit on the DVD, and then magically decompress them to full HD off of the DVD. The up-rezzing chips can do some magic, but we're talking Houdini level work here.

                 

                The common complaint is "when I take my AVCHD to DVD, PrE does something wrong, 'cause my output looks less sharp, even on my 60" HD TV." Yes, that is the way it is, when you are working with about 1/4 of the pixels.

                 

                Hunt

                • 5. Re: How can I cut up a video file into smaller bits?
                  Ted Smith Level 3

                  Yes I am fully aware of all that.

                  What I was originally asking was the best way of getting the best possible result in converting.

                   

                  But siomehow as, often in this forum, I got answers that suggested I should not be doing it!

                   

                  I personally make BD's only for myself but unfortunately many poor people, including relations, still dont have a 1900x1080 TV and BD player!

                  The reason why most people with a HD camera should shoot in HD is they will eventually get a BD player if they dont have one how.

                   

                  My tests on converters says that PE9 is hopeless in trying to make a standard DVD form a 1900x1080 original. The result is really horrible when played on a BD player and upscaled as you suggested compared with a DVD made form original 720x576 material. (Blurry and jagged diagonal lines)

                   

                  On the other hand the 4Media result is almost the same and you can't tell the difference on an old video CRT TV..

                   

                  Conclusion, if people complain about poor conversions. it's the tools, not the principle!