HDV and Jitter


    Jul 26 2006 | 7:52 pm
    What is the current status of inputting HDV (1080i) into Jitter? We are considering the use of HDV for a video installation, with minimal Jitter processing, outputing the signal at 16:9 to a 1024 X 768 data projector using a dual 2 Gig Mac.
    Thanks,
    Randall Packer

    • Jul 26 2006 | 8:27 pm
      On Jul 26, 2006, at 12:52 PM, Randall Packer wrote:
      > What is the current status of inputting HDV (1080i) into Jitter? We > are considering the use of HDV for a video installation, with > minimal Jitter processing, outputing the signal at 16:9 to a 1024 X > 768 data projector using a dual 2 Gig Mac.
      Unfortunately, there is no QT input component for HDV. iMovie and FCP make use of a private API to interface with these cameras. We may investigate HDV input at some point in the future, but certainly won't have it available anytime soon, unless some other software developer makes an HDV QT input component. Also note that there will possibly be greater latency with HDV which uses interframe (temporal) compression, unlike DV or DVCPro HD.
      I have had success using the QT input component for DVCPro HD (provided with FCP) with the Panasonic AG-HVX200. However, note that over firewire any 720 DVCProHD signal is delivered on top of a 1080 DVCProHD signal. Since Jitter doesn't have special DVCPro HD code to unpack this data, it looks like digital barf if streaming at 720 DVCProHD into Jitter. I am able to stream and draw to a window the 1080 DVCPro HD signal, however, in Jitter even on a 1.67GHz G4 AluBook. These cameras are obviously more expensive than the HDV cameras out there, but they provide better quality images, with higher quality chroma sampling (4:2:2 instead of 4:2:0), less intraframe (spatial) compression, and no interframe (temporal) compression.
      Also of note, if I do capture DVCPro HD data for playback (I use FCP to grab the 720p data), I typically convert to high quality photo jpeg for significantly faster playback performance (30fps for photo jpeg vs 8 fps in a slab based patch I use on my 1.67 G4 AluBook), and compatibility on machines without FCP installed. If you are trying to playback DVCPro HD in jit.qt.movie, make sure you either have the highquality attribute enabled or have set it in the media file itself, just as you would for DV. Otherwise it renders as preview quailty.
      I believe you might need to also export to Photo JPEG for HDV data just to play in Jitter, and even if it's not a requirement, you might get faster framerates if you do.
      For future reference, this is better suited for the Jitter list.
      -Joshua
    • Jul 26 2006 | 9:53 pm
      Moving this thread to Jitter, as per Joshua's suggestion...