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Best One-Stop URL for Vlog/Podcast Newbie?

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  • Jan McLaughlin
    Want to publish a single link for folks who know absolutely nothing about getting set up to subscribe to Vlog & Podcasts. What are your favorite tutorial
    Message 1 of 13 , Apr 30, 2005
      Want to publish a single link for folks who know absolutely nothing
      about getting set up to subscribe to Vlog & Podcasts.

      What are your favorite tutorial sites?

      Jan


      --
      "It isn't done alone" - Ian Watson, Love Detective & Staff Writer
      http://fauxpress.blogspot.com
    • Adam Quirk
      freevlog.blogspot.com videoblogging.info Podcasts? Huh?
      Message 2 of 13 , Apr 30, 2005
        freevlog.blogspot.com
        videoblogging.info

        Podcasts? Huh?

        On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
        > Want to publish a single link for folks who know absolutely nothing
        > about getting set up to subscribe to Vlog & Podcasts.
        >
        > What are your favorite tutorial sites?
      • Jan McLaughlin
        Hey, baby, I m multi-media oriented. Sue me. ... Jan P.S. Thanks for the links.
        Message 3 of 13 , Apr 30, 2005
          Hey, baby, I'm multi-media oriented.

          Sue me.

          :)

          Jan

          P.S. Thanks for the links.

          On Apr 30, 2005, at 2:32 PM, Adam Quirk wrote:

          > freevlog.blogspot.com
          > videoblogging.info
          >
          > Podcasts? Huh?
          >
          > On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
          >> Want to publish a single link for folks who know absolutely nothing
          >> about getting set up to subscribe to Vlog & Podcasts.
          >>
          >> What are your favorite tutorial sites?
          >
          >
          >
          > Yahoo! Groups Links
          >
          >
          >
          >
          >
          >
          >
        • Jason Romney
          Hi Folks, I ve uploaded to www.netvideo.com.au an H264 edition of the Netvideo episode which is about Tiger, having encoded it on the Tiger I ve installed
          Message 4 of 13 , Apr 30, 2005
            Hi Folks,

            I've uploaded to www.netvideo.com.au an H264 edition of the Netvideo episode
            which is about Tiger, having encoded it on the Tiger I've installed
            (following an upgrade to Quicktime 7).

            http://homepage.mac.com/jason_romney/JasonSwifte290405.3gp

            I'm having a lot of trouble getting the framerate right in H263 encodes, by
            the way, and would appreciate anyone's insights here. H264 works fine when I
            play it back, but H263 seems to only show the first frames of the video and
            then somehow get "stuck" on a frame and refuse to show the rest of the
            video. The audio is fine. Does anyone have some H263 video encode
            configuration settings that work well for them? And on which cellphones have
            people tested H263, and of course, also, H264 encodes, for good smooth
            playback so far?

            By the way, overall, I'm delighted with Tiger, but I've had to update
            numerous pieces of software at considerable expense (eg Timbuktu Pro). In
            addition, some critical software I use often, such as BlogWaveStudio (which
            I use to publish my Web site), quits in Tiger and a new version 1.9.1 isn't
            expected for a week or two...so its back to manual coding for a while.

            Kind regards,
            Jason Romney
          • Josh Wolf
            I ve got some video from the Tiger Launch at the SF Apple store in H264 on my blog. I put it up at 640x480 in the hopes that I could make a file that s
            Message 5 of 13 , Apr 30, 2005
              I've got some video from the Tiger Launch at the SF Apple store in
              H264 on my blog. I put it up at 640x480 in the hopes that I could
              make a file that's manageable, and yet looks good for full-screen
              video. No luck... oh well... I think I agree with Michael that 3IVX
              seems to be just as good as H264 for the most part. It certainly is
              more intuitive when it comes to tweaking the preferences for the codec.

              Here's the clip from the launch:
              http://tinyurl.com/de3ku

              Josh

              On Apr 30, 2005, at 9:38 PM, Jason Romney wrote:

              > Hi Folks,
              >
              > I've uploaded to www.netvideo.com.au an H264 edition of the
              > Netvideo episode
              > which is about Tiger, having encoded it on the Tiger I've installed
              > (following an upgrade to Quicktime 7).
              >
              > http://homepage.mac.com/jason_romney/JasonSwifte290405.3gp
              >
              > I'm having a lot of trouble getting the framerate right in H263
              > encodes, by
              > the way, and would appreciate anyone's insights here. H264 works
              > fine when I
              > play it back, but H263 seems to only show the first frames of the
              > video and
              > then somehow get "stuck" on a frame and refuse to show the rest of the
              > video. The audio is fine. Does anyone have some H263 video encode
              > configuration settings that work well for them? And on which
              > cellphones have
              > people tested H263, and of course, also, H264 encodes, for good smooth
              > playback so far?
              >
              > By the way, overall, I'm delighted with Tiger, but I've had to update
              > numerous pieces of software at considerable expense (eg Timbuktu
              > Pro). In
              > addition, some critical software I use often, such as
              > BlogWaveStudio (which
              > I use to publish my Web site), quits in Tiger and a new version
              > 1.9.1 isn't
              > expected for a week or two...so its back to manual coding for a while.
              >
              > Kind regards,
              > Jason Romney
              >
              >
              >
              >
              >
              > Yahoo! Groups Links
              > To visit your group on the web, go to:
              > http://groups.yahoo.com/group/videoblogging/
              >
              > To unsubscribe from this group, send an email to:
              > videoblogging-unsubscribe@yahoogroups.com
              >
              > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
              >


              ____________________________________________
              "Don't hate the media, become the media."- Jello Biafra
            • joel carner
              jan - don t forget freevlog.org joel http://joelart.blogspot.com
              Message 6 of 13 , Apr 30, 2005
                jan - don't forget freevlog.org

                joel
                http://joelart.blogspot.com

                On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
                > Hey, baby, I'm multi-media oriented.
                >
                > Sue me.
                >
                > :)
                >
                > Jan
                >
                > P.S. Thanks for the links.
                >
                > On Apr 30, 2005, at 2:32 PM, Adam Quirk wrote:
                >
                > > freevlog.blogspot.com
                > > videoblogging.info
                > >
                > > Podcasts? Huh?
                > >
                > > On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
                > >> Want to publish a single link for folks who know absolutely nothing
                > >> about getting set up to subscribe to Vlog & Podcasts.
                > >>
                > >> What are your favorite tutorial sites?
                > >
                > >
                > >
                > > Yahoo! Groups Links
                > >
                > >
                > >
                > >
                > >
                > >
                > >
                >
                > Yahoo! Groups Links
                >
                >
                >
                >
                >
              • Jan McLaughlin
                Thanks, Joel! Jan
                Message 7 of 13 , May 1, 2005
                  Thanks, Joel!
                  Jan

                  On May 1, 2005, at 1:49 AM, joel carner wrote:

                  > jan - don't forget freevlog.org
                  >
                  > joel
                  > http://joelart.blogspot.com
                  >
                  > On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
                  >> Hey, baby, I'm multi-media oriented.
                  >>
                  >> Sue me.
                  >>
                  >> :)
                  >>
                  >> Jan
                  >>
                  >> P.S. Thanks for the links.
                  >>
                  >> On Apr 30, 2005, at 2:32 PM, Adam Quirk wrote:
                  >>
                  >>> freevlog.blogspot.com
                  >>> videoblogging.info
                  >>>
                  >>> Podcasts? Huh?
                  >>>
                  >>> On 4/30/05, Jan McLaughlin <vze4pnhk@...> wrote:
                  >>>> Want to publish a single link for folks who know absolutely nothing
                  >>>> about getting set up to subscribe to Vlog & Podcasts.
                  >>>>
                  >>>> What are your favorite tutorial sites?
                  >>>
                  >>>
                  >>>
                  >>> Yahoo! Groups Links
                  >>>
                  >>>
                  >>>
                  >>>
                  >>>
                  >>>
                  >>>
                  >>
                  >> Yahoo! Groups Links
                  >>
                  >>
                  >>
                  >>
                  >>
                  >
                  >
                  >
                  > Yahoo! Groups Links
                  >
                  >
                  >
                  >
                  >
                  >
                  >
                • Jan McLaughlin
                  Josh, My G4 QT6 Pro came back with a QT doesn t have the software error when accessing the vid page. Jan [growling like a Tiger]
                  Message 8 of 13 , May 1, 2005
                    Josh,

                    My G4 QT6 Pro came back with a "QT doesn't have the software" error
                    when accessing the vid page.

                    Jan
                    [growling like a Tiger]

                    On May 1, 2005, at 1:40 AM, Josh Wolf wrote:

                    > I've got some video from the Tiger Launch at the SF Apple store in
                    > H264 on my blog. I put it up at 640x480 in the hopes that I could
                    > make a file that's manageable, and yet looks good for full-screen
                    > video. No luck... oh well... I think I agree with Michael that 3IVX
                    > seems to be just as good as H264 for the most part. It certainly is
                    > more intuitive when it comes to tweaking the preferences for the codec.
                    >
                    > Here's the clip from the launch:
                    > http://tinyurl.com/de3ku
                    >
                    > Josh
                    >
                    > On Apr 30, 2005, at 9:38 PM, Jason Romney wrote:
                    >
                    >> Hi Folks,
                    >>
                    >> I've uploaded to www.netvideo.com.au an H264 edition of the
                    >> Netvideo episode
                    >> which is about Tiger, having encoded it on the Tiger I've installed
                    >> (following an upgrade to Quicktime 7).
                    >>
                    >> http://homepage.mac.com/jason_romney/JasonSwifte290405.3gp
                    >>
                    >> I'm having a lot of trouble getting the framerate right in H263
                    >> encodes, by
                    >> the way, and would appreciate anyone's insights here. H264 works
                    >> fine when I
                    >> play it back, but H263 seems to only show the first frames of the
                    >> video and
                    >> then somehow get "stuck" on a frame and refuse to show the rest of the
                    >> video. The audio is fine. Does anyone have some H263 video encode
                    >> configuration settings that work well for them? And on which
                    >> cellphones have
                    >> people tested H263, and of course, also, H264 encodes, for good smooth
                    >> playback so far?
                    >>
                    >> By the way, overall, I'm delighted with Tiger, but I've had to update
                    >> numerous pieces of software at considerable expense (eg Timbuktu
                    >> Pro). In
                    >> addition, some critical software I use often, such as
                    >> BlogWaveStudio (which
                    >> I use to publish my Web site), quits in Tiger and a new version
                    >> 1.9.1 isn't
                    >> expected for a week or two...so its back to manual coding for a while.
                    >>
                    >> Kind regards,
                    >> Jason Romney
                    >>
                    >>
                    >>
                    >>
                    >>
                    >> Yahoo! Groups Links
                    >> To visit your group on the web, go to:
                    >> http://groups.yahoo.com/group/videoblogging/
                    >>
                    >> To unsubscribe from this group, send an email to:
                    >> videoblogging-unsubscribe@yahoogroups.com
                    >>
                    >> Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
                    >>
                    >
                    >
                    > ____________________________________________
                    > "Don't hate the media, become the media."- Jello Biafra
                    >
                    >
                    >
                    >
                    > Yahoo! Groups Links
                    >
                    >
                    >
                    >
                    >
                    >
                    >
                  • Josh Wolf
                    Jan, you re not missing much -- but, since you asked -- I m putting up a 3ivx version right now... Josh http://thisrevolution.blogspot.com ...
                    Message 9 of 13 , May 1, 2005
                      Jan, you're not missing much -- but, since you asked -- I'm putting
                      up a 3ivx version right now...

                      Josh

                      http://thisrevolution.blogspot.com


                      On May 1, 2005, at 1:18 AM, Jan McLaughlin wrote:

                      > Josh,
                      >
                      > My G4 QT6 Pro came back with a "QT doesn't have the software" error
                      > when accessing the vid page.
                      >
                      > Jan
                      > [growling like a Tiger]
                      >
                      > On May 1, 2005, at 1:40 AM, Josh Wolf wrote:
                      >
                      > > I've got some video from the Tiger Launch at the SF Apple store in
                      > > H264 on my blog. I put it up at 640x480 in the hopes that I could
                      > > make a file that's manageable, and yet looks good for full-screen
                      > > video. No luck... oh well... I think I agree with Michael that 3IVX
                      > > seems to be just as good as H264 for the most part. It certainly is
                      > > more intuitive when it comes to tweaking the preferences for the
                      > codec.
                      > >
                      > > Here's the clip from the launch:
                      > > http://tinyurl.com/de3ku
                      > >
                      > > Josh
                      > >
                      > > On Apr 30, 2005, at 9:38 PM, Jason Romney wrote:
                      > >
                      > >> Hi Folks,
                      > >>
                      > >> I've uploaded to www.netvideo.com.au an H264 edition of the
                      > >> Netvideo episode
                      > >> which is about Tiger, having encoded it on the Tiger I've installed
                      > >> (following an upgrade to Quicktime 7).
                      > >>
                      > >> http://homepage.mac.com/jason_romney/JasonSwifte290405.3gp
                      > >>
                      > >> I'm having a lot of trouble getting the framerate right in H263
                      > >> encodes, by
                      > >> the way, and would appreciate anyone's insights here. H264 works
                      > >> fine when I
                      > >> play it back, but H263 seems to only show the first frames of the
                      > >> video and
                      > >> then somehow get "stuck" on a frame and refuse to show the rest
                      > of the
                      > >> video. The audio is fine. Does anyone have some H263 video encode
                      > >> configuration settings that work well for them? And on which
                      > >> cellphones have
                      > >> people tested H263, and of course, also, H264 encodes, for good
                      > smooth
                      > >> playback so far?
                      > >>
                      > >> By the way, overall, I'm delighted with Tiger, but I've had to
                      > update
                      > >> numerous pieces of software at considerable expense (eg Timbuktu
                      > >> Pro). In
                      > >> addition, some critical software I use often, such as
                      > >> BlogWaveStudio (which
                      > >> I use to publish my Web site), quits in Tiger and a new version
                      > >> 1.9.1 isn't
                      > >> expected for a week or two...so its back to manual coding for a
                      > while.
                      > >>
                      > >> Kind regards,
                      > >> Jason Romney
                      > >>
                      > >>
                      > >>
                      > >>
                      > >>
                      > >> Yahoo! Groups Links
                      > >> To visit your group on the web, go to:
                      > >> http://groups.yahoo.com/group/videoblogging/
                      > >>
                      > >> To unsubscribe from this group, send an email to:
                      > >> videoblogging-unsubscribe@yahoogroups.com
                      > >>
                      > >> Your use of Yahoo! Groups is subject to the Yahoo! Terms of
                      > Service.
                      > >>
                      > >
                      > >
                      > > ____________________________________________
                      > > "Don't hate the media, become the media."- Jello Biafra
                      > >
                      > >
                      > >
                      > >
                      > > Yahoo! Groups Links
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      > >
                      >
                      >
                      > Yahoo! Groups Links
                      > To visit your group on the web, go to:
                      > http://groups.yahoo.com/group/videoblogging/
                      >
                      > To unsubscribe from this group, send an email to:
                      > videoblogging-unsubscribe@yahoogroups.com
                      >
                      > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
                      >


                      ____________________________________________
                      "Don't hate the media, become the media."- Jello Biafra
                    • Steve Watkins
                      Thanks for the samples. OK well I see your tests as being extremely promising for h.264. If I am thinking correctly Your h.264 example is handling 8 times more
                      Message 10 of 13 , May 1, 2005
                        Thanks for the samples.

                        OK well I see your tests as being extremely promising for h.264.

                        If I am thinking correctly Your h.264 example is handling 8 times more information than
                        the 3ivx sample:

                        Your 3ivx is at 320x240 wheras the h.264 at 640x480 has 4 times as many pixels. And
                        the framerate on your H.264 clip is 30fps as opposed to 15fps in the 3ivx example. So
                        thats 8 times as much raw video being handled in the h.264 clip, but the filesize is only
                        twice as big as the 3ivx.

                        have I got that right?

                        The quality of your h.264 clip is somewhat spoiled by interlacing issues. I can see the
                        dreaded jaggedy lines at various points.

                        Anyway I now own a Mac mini, hoorah, got tiger on it and just bought quicktime 7 pro 10
                        minutes ago, so I will see what tests I can do to help evaluate h.264 further.

                        The main problem so far is that I have not seen clips in 3ivx and h.264 that can be directly
                        compared due to people picking different resolutions etc.

                        Jason Romney, cheers for the H.264 clip yopu have done too. Its in 3gp format at
                        resolutions designed for mobile phones, so it doesnt look very nice on my computer.

                        Cheers

                        Steve of Elbows

                        --- In videoblogging@yahoogroups.com, Josh Wolf <inthecity@s...> wrote:
                        > Jan, you're not missing much -- but, since you asked -- I'm putting
                        > up a 3ivx version right now...
                        >
                        > Josh
                        >
                        > http://thisrevolution.blogspot.com
                        >
                        >
                        > On May 1, 2005, at 1:18 AM, Jan McLaughlin wrote:
                        >
                        > > Josh,
                        > >
                        > > My G4 QT6 Pro came back with a "QT doesn't have the software" error
                        > > when accessing the vid page.
                        > >
                        > > Jan
                        > > [growling like a Tiger]
                        > >
                        > > On May 1, 2005, at 1:40 AM, Josh Wolf wrote:
                        > >
                        > > > I've got some video from the Tiger Launch at the SF Apple store in
                        > > > H264 on my blog. I put it up at 640x480 in the hopes that I could
                        > > > make a file that's manageable, and yet looks good for full-screen
                        > > > video. No luck... oh well... I think I agree with Michael that 3IVX
                        > > > seems to be just as good as H264 for the most part. It certainly is
                        > > > more intuitive when it comes to tweaking the preferences for the
                        > > codec.
                        > > >
                        > > > Here's the clip from the launch:
                        > > > http://tinyurl.com/de3ku
                        > > >
                        > > > Josh
                        > > >
                        > > > On Apr 30, 2005, at 9:38 PM, Jason Romney wrote:
                        > > >
                        > > >> Hi Folks,
                        > > >>
                        > > >> I've uploaded to www.netvideo.com.au an H264 edition of the
                        > > >> Netvideo episode
                        > > >> which is about Tiger, having encoded it on the Tiger I've installed
                        > > >> (following an upgrade to Quicktime 7).
                        > > >>
                        > > >> http://homepage.mac.com/jason_romney/JasonSwifte290405.3gp
                        > > >>
                        > > >> I'm having a lot of trouble getting the framerate right in H263
                        > > >> encodes, by
                        > > >> the way, and would appreciate anyone's insights here. H264 works
                        > > >> fine when I
                        > > >> play it back, but H263 seems to only show the first frames of the
                        > > >> video and
                        > > >> then somehow get "stuck" on a frame and refuse to show the rest
                        > > of the
                        > > >> video. The audio is fine. Does anyone have some H263 video encode
                        > > >> configuration settings that work well for them? And on which
                        > > >> cellphones have
                        > > >> people tested H263, and of course, also, H264 encodes, for good
                        > > smooth
                        > > >> playback so far?
                        > > >>
                        > > >> By the way, overall, I'm delighted with Tiger, but I've had to
                        > > update
                        > > >> numerous pieces of software at considerable expense (eg Timbuktu
                        > > >> Pro). In
                        > > >> addition, some critical software I use often, such as
                        > > >> BlogWaveStudio (which
                        > > >> I use to publish my Web site), quits in Tiger and a new version
                        > > >> 1.9.1 isn't
                        > > >> expected for a week or two...so its back to manual coding for a
                        > > while.
                        > > >>
                        > > >> Kind regards,
                        > > >> Jason Romney
                        > > >>
                        > > >>
                        > > >>
                        > > >>
                        > > >>
                        > > >> Yahoo! Groups Links
                        > > >> To visit your group on the web, go to:
                        > > >> http://groups.yahoo.com/group/videoblogging/
                        > > >>
                        > > >> To unsubscribe from this group, send an email to:
                        > > >> videoblogging-unsubscribe@yahoogroups.com
                        > > >>
                        > > >> Your use of Yahoo! Groups is subject to the Yahoo! Terms of
                        > > Service.
                        > > >>
                        > > >
                        > > >
                        > > > ____________________________________________
                        > > > "Don't hate the media, become the media."- Jello Biafra
                        > > >
                        > > >
                        > > >
                        > > >
                        > > > Yahoo! Groups Links
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > > >
                        > >
                        > >
                        > > Yahoo! Groups Links
                        > > To visit your group on the web, go to:
                        > > http://groups.yahoo.com/group/videoblogging/
                        > >
                        > > To unsubscribe from this group, send an email to:
                        > > videoblogging-unsubscribe@yahoogroups.com
                        > >
                        > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
                        > >
                        >
                        >
                        > ____________________________________________
                        > "Don't hate the media, become the media."- Jello Biafra
                      • Michael Verdi
                        ... Hey Steve, Actually, doubling the framerate doesn t double the file size. In fact it only produces a slight increase. This is something that seems very
                        Message 11 of 13 , May 1, 2005
                          On May 1, 2005, at 11:18 AM, Steve Watkins wrote:

                          > Thanks for the samples.
                          >
                          > OK well I see your tests as being extremely promising for h.264.
                          >
                          > If I am thinking correctly Your h.264 example is handling 8 times
                          > more information than
                          > the 3ivx sample:
                          >
                          > Your 3ivx is at 320x240 wheras the h.264 at 640x480 has 4 times as
                          > many pixels. And
                          > the framerate on your H.264 clip is 30fps as opposed to 15fps in
                          > the 3ivx example. So
                          > thats 8 times as much raw video being handled in the h.264 clip,
                          > but the filesize is only
                          > twice as big as the 3ivx.
                          >
                          > have I got that right?
                          >

                          Hey Steve,
                          Actually, doubling the framerate doesn't double the file size. In
                          fact it only produces a slight increase. This is something that
                          seems very counter intuitive but I've run across it before. I have
                          no idea why this is. Does anybody out there know?
                          Thanks,

                          -Verdi
                          http://michaelverdi.com
                          http://freevlog.blogspot.com
                        • Steve Watkins
                          Yes its because of the way many forms of compression works. They record complete frames of video only occasionally (keyframes) and other frames are stored
                          Message 12 of 13 , May 1, 2005
                            Yes its because of the way many forms of compression works. They record complete
                            frames of video only occasionally (keyframes) and other frames are stored like ' what has
                            changed since the last frame' rather than the entire frame being stored.

                            If you tell the encoder to make video of a certain datarate, it cant go above that no matter
                            what framerate and resolution you use, so the file wont be any larger, just more
                            compressed and more ugly.

                            When I was talking about 4 and 8 times more information, I was talking about
                            uncompressed video, how much 'raw information' the video encoder has to squeeze into
                            whatever datarate you have specified.

                            So returnign to the tiger store opening video as an example:

                            The datarate for the 3ivx version is 258kbits/sec

                            The datarate for the h264 version has beeen set to around 658kbits/sec

                            These numbers probably include the audio too, but I wont worry about that for now.

                            So the h.264 codec has been given just over twice as many bits per second in which to
                            store the video. But it is being told to store the video with 4 times as many pixels and
                            twice the number of frames = 8 times more raw video information in just over twice as
                            much space.

                            Anyway the words Ive used to explain this has probably made my explanation not 100%
                            technically accurate, but hopefully its of some use.

                            A starting point for testing how good h.264 really is would be to encode with exactly the
                            same framerate, datarate, keyframe settings, resolution and audio settings as you already
                            use in 3ivx. Does it look better than 3ivx then?

                            More from me later once Ive actually managed to do testing on my mac.

                            Cheers

                            Steve of Elbows

                            --- In videoblogging@yahoogroups.com, Michael Verdi <michael@m...> wrote:
                            > Hey Steve,
                            > Actually, doubling the framerate doesn't double the file size. In
                            > fact it only produces a slight increase. This is something that
                            > seems very counter intuitive but I've run across it before. I have
                            > no idea why this is. Does anybody out there know?
                            > Thanks,
                            >
                            > -Verdi
                            > http://michaelverdi.com
                            > http://freevlog.blogspot.com
                          • Adrian Miles
                            around the 1/5/05 Michael Verdi mentioned about Re: [videoblogging] ... 1. frame rate can affect file size but it is not symmetrical (double fps doesn t =
                            Message 13 of 13 , May 4, 2005
                              around the 1/5/05 Michael Verdi mentioned about Re: [videoblogging]
                              Re: H264 and quicktime 7 that:
                              >Actually, doubling the framerate doesn't double the file size. In
                              >fact it only produces a slight increase. This is something that
                              >seems very counter intuitive but I've run across it before. I have
                              >no idea why this is. Does anybody out there know?

                              1. frame rate can affect file size but it is not symmetrical (double
                              fps doesn't = double size). This is due to delta frames, key frames
                              and frame differencing.

                              2. this is *basic* compression.

                              3. A good modern codec (eg H.264) should be allowed to auto insert
                              keyframes. If you override this you're going to produce stoopid sizes.

                              4. a key frame is the codec saying, hey, I need to remember *all* the
                              info for this frame, because it is so different from the last one.
                              Then the codec only remembers what is different from that key frame
                              for the next n frames. Until *it* decides it needs a new keyframe.
                              (this is why you let it decide.) Very good codecs do this forwards
                              and backwards (so how different from last keyframe, how different
                              from next keyframe).

                              5. this is why very good codecs do 2 passes, they have to analyse all
                              this first.

                              6. if you film yourself not moving, against a still background, you
                              can compress down to about 1 kbit a second and it will look great
                              (I'm serious). If you jump around all over the place then more
                              keyframes are needed, there is much more differencing, file size is
                              bigger.

                              7. However, frame size makes a big difference. double frame size (say
                              160 x 120 to 320 x 240) and you quadruple the amount of data required.

                              8. However, dropping frame rate can also help since it doesn't have
                              to draw so much, and you get less key frames (potentially).

                              9. Never increase the frame rate in compression.

                              10. Compression is lossy, it throws data away. If you try to add data
                              then you are asking the codec to invent data it doesn't have. It
                              would be like compressing to jpeg in photoshop, then converting it to
                              32bit RGB, and complaining about the crappy quality of your eps
                              artwork. :-)

                              11. Never increase the frame size in compression.

                              12. Never increase anything in compression.

                              13. If you manually set keyframes (say every 5 seconds), and you've
                              got 10 seconds of a vase, then you've added a pile of data that is
                              100% irrelevant and unneeded.

                              14. If you are serving off RTSP (real time) then you do manually
                              insert keyframes. Videbloggers don't use rtsp, we use http (for very
                              good reasons).
                              --
                              cheers
                              Adrian Miles
                              ____________
                              hypertext.RMIT
                              http://hypertext.rmit.edu.au/vlog
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