3 Replies Latest reply on Apr 24, 2013 9:06 AM by Qengineering

    quality loss


      Hi there,


      I'm hoping someone can help me with this work flow as I'm new to post production work.


      We stream and record public events 3-4 times a week using Wirecast as our capture, record and streaming software (basically you can record to disk the livestream with all the powerpoint shots, graphics etc so it saves you having to add them after), the livestream is fine, the problem is the recorded file. As wirecast has to do a live encode for the streaming and recording it has to do 2 x encodes at different settings.


      I've recorded to QuickTime and Flash and both have given bad results considering the dimensions are 1280 x 720. The result is bad but after doing some simple edits in iMovie the exported file is even worst. What i would like to know is what is best quality codec to use to record to if the end format will be flash and would premiere pro be able to edit a H264 file and then export it without losing quality? I've seen in some forums that flash isn't very good for post production work and it can take forever to import into iMovie because of the transcodeing (not sure if that's the right terminology) and i know it's best practice to keep the native record and then edit from that but i don't have the luxury of being able to edit the recording from a camera.


      AIC and ProRes have been mentioned but the file sizes are massive.


      Any suggestions would be much appreciated


      Wirecast 4.2.6
      MBP Retina  10.7.4
      2.5ghz Intel core i7
      8gb RAM
      Cannon HD40

        • 1. Re: quality loss
          Qengineering Level 3

          Telestream is an excellent company and you may want to ask this question in their forums as well.


          Avoid AIC, it is a relatively old technology that has no place in newer video applications.


          I'm not aware of any issues with Mainconcept H.264 files in Premiere, so that would be my first choice.

          The H.264 files should be an accurate representation (quality) of the streamed video. If they are not, that would be a Wirecast issue, possibly caused by under powered computer or slow hard drive storage especially considering your doing two simultaneous HD encodes.


          If you experience image degradation using the H.264 files in Premiere you should consider transcoding to Apple ProRes (LT). The files are bigger than H.264 but you will see no degradation. You can always delete the transcoded files when completely done and save the H.264 as archive originals.

          • 2. Re: quality loss
            Balmar100 Level 1

            thanks for the reply. I've never used premiere pro so i wanted to check that importing a h264 file and then doing some simple edits and exporting a h264 wouldn't cause any quality loss? I'm not looking to change the resoltuion or aspect ratio just split the files and then export the same files


            the only output i have is a HDMI out on the MBP so i was thinking of using the external monitor output in wirecast to send the stream to a hyperdeck shuttle so i have a top quality recording inculding all the graphics and video conference shots in one uncompressed file, or a compressed but good quality h264 file.



            Would that work?

            • 3. Re: quality loss
              Qengineering Level 3

              In theory recording to the Hyperdeck Shuttle should work. My one concern would be sending a non-standard video signal to a recorder that may only accept ultra-stable broadcast standard video. I see the Shuttle accepts 720p60 and 1080PfS30 (as opposed to 59.94 and 29.97 respectively) but I could not say if the MBP supplies a stable enough signal at those specs. That would be a question for Blackmagic.