7 Replies Latest reply on Oct 12, 2011 5:34 AM by VidMuze

    Video compression for web. H264 codec.


      Hello to everyone!

      I would be gratefull If someone can help me with some advice on the following matter:

      Who can I compress a video which is shot with dslr camera, at 640x424p, 25fps, so that 20 seconds of video do not exceed 1mb.

      The final video has to be 512pixels in height and 340 in width, good quality under 1mb.

      I usually export this kind of web files using h264. For this job I modified the biterates so that the video does not exceed 1mb but all resulted in poor quality.

      The satisfactory quality of the video is reached only after 4mbs(biterate/vbr pass2), in this case the filesize is over 5mb so again no good.


      Please help?

        • 1. Re: Video compression for web. H264 codec.
          andreinemo Level 1

          correction: How can I compress..sorry.

          • 2. Re: Video compression for web. H264 codec.
            Jim_Simon Level 8

            Here's the thing.  File size is determined largely by only two factors, bitrate and duration.  How many bits per second times how many seconds.  Things like resolution, frame rate and codec don't really affect the file size all that much.


            Having said that, in my experience, H.264 is pretty much the best quality codec out there right now.  Any other codec at the same bitrate just won't look as good.


            So, you know the bitrate you need to keep it under 1MB.  And you're currently using the best codec available.  If it doesn't look acceptable, you're only real option is to abandon the 1MB limit, or to make it even shorter than 20 seconds so you can increase the bitrate.

            1 person found this helpful
            • 3. Re: Video compression for web. H264 codec.
              andreinemo Level 1

              Thank you for your contribution , Jim. But the thing that made me question that compression is one h264 encoder software I found on the internet. The encoder calculates by itself de biterate and all other settings. The result is much better than Premiere exports. I made it with my file up to 1.7mb. Premiere export was 3-5mb and worse quality so there has to be something more to this.

              What do you think?

              • 4. Re: Video compression for web. H264 codec.
                andreinemo Level 1

                And another thing I noticed in Premiere: I usually do a small edit of about 20 seconds from 3-4 clips. Well, this time I compressed the three clips before editing them in premiere. I used the h.264 encoder I talked about and it reduced my filesize to half for each of them(no  visible quality loss). Now I imported the 3 files(reduced) in Premiere and the 20 seconds of editing still export as the same big size it was before encoding and reducing the clips. More interresting is that all three clips together have about a minute of footage and they get pretty close to the filesize that the 20 second export video has.


                I did another experiment and imported one video file in Premiere and without modifing the content, i wanted to export it to see what happens with the filesize after entering and exporting with premiere. The export was bigger in filesize and lower in quality. One thing changed though: I imported a mov and exported an mp4. So how come my dslr camera exports such good quality videos with such small file size. Is mov better than mp4? If the software camera did such great job compressing the videos, why can't I find a computer software that does the same?


                I appreciate your time!

                Thank you!

                • 5. Re: Video compression for web. H264 codec.
                  Jim_Simon Level 8

                  Different encoders can perform better or worse than other encoders at the same bitrate.  The general consensus at this time is that the x264 encoder is one of the best around.  Adobe licenses the MainConcept encoder.  So it's no surprise when you say the Internet encoder did a better job.


                  Still the basic idea is the same.  File size is determined by bitrate and duration.  And h.264 is probably the best codec around at this time.  If an external encoder does a better job than Premiere Pro's encoder, go ahead and use that.  I use the free HC Encoder for all my MPEG2 transcodes for precisely that reason.


                  MOV and MP4 are simply containers.  The codec inside is what will determine the qulaity.

                  1 person found this helpful
                  • 6. Re: Video compression for web. H264 codec.
                    andreinemo Level 1

                    Thank you very much, Jim!

                    • 7. Re: Video compression for web. H264 codec.
                      VidMuze Level 1

                      Here's a tutorial I did on export settings you may be able to learn some helpful tips.


                      Hope it helps.