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Green Frames? That G5 render is not as good as your Intel does in ProRes.
Since I was asked this question in another thread, rather than hijack the HDCam offline I will post this info as part of something new.
[gary adcock] “You do know that prores software encoded on a non intel machine does not have the same level of quality as the same file processed in the same way on an intel machine.
“ProRes was designed to be an intermediate codec to keep the postproduction workflow data at 10bit quality, yet at a low enough bandwidth to be usable. It is considered to be a variable bit rate codec, where the amount of compression varies based on frame rate, inter-frame differences and the like. Much like h.264 for iTunes, it operates as a scalar codec, with the ability for full frame playback previews from ½ or ¼ size frame data, lowering the data throughput while maintaining quality”
(from an article I wrote on prores).So, on a non intel machine, because of ProRes’s ability to handle data in VBR, means that differences between encoding on various CPU’s. ProRes did not even originally run on non intel machines, and it nearly impossible to directly capture to without the intel’s sheer number crunching power. Hence the reason so many post here lately have been lamenting the “green frames” on playback issue.
Those frames are a hiccup in the CPU’s processing that causes the compression skip. On Non intel machines my tests on 4 different G5 config’s showed not one was using anything but the 1/4 rez playback. You can see this for yourself if working on a kona card- open the Kona control panel and look at the frame buffer indicator – if the word ProRes is indicated in red- you are NOT getting full frame playback.
OK here you go. Gary’s rules for ProRes
1) Use it- it is by far the best codec FCP has ever had, it blows DVCPROHD out of the water in post.
it wants a new machine if you are not on intel- it’s about time.2) ProRes HQ should only used when Captured Via Hardware when creating it from any camera except RED and the PHANTOM. Those are ONLY 2 Tapeless cameras that can actually use the advantages that ProRes HQ offers when working in a tapeless system since they actually record more than 10 bits as data.
3) Software Conversions from previously captured materials or data transfered formats do not need anything more than the Standard Version on ProRes. The reason for this is that camera formats are 8bit, ProRes is 10bit. With the HQ version the CPU is actively interpreting all 256 levels of grey on encode but passing that back out re-interpreted with all 1024 levels on output, that is one HUGE Mathematical Processing task.
4) With the Standard version of ProRes, that data is not re-interpreted on output until the process actually asks the CPU to handle the content in 10bit by adding filters, efx, or color correction. So normal playback of your timeline is unaffected until you do something to it.
5) Every thin raster camera (both HDV & DVCPROHD) will deliver better results when they content is played out via the camera mfg’s hardware- because the video has to be SMPTE compliant, the process using specifically customized decompression tools will ALWAYS beat a software conversion of the same content.
On a suitably powered intel machine I have had no issues with ProRes, I have ingested over 100TB (NOT a typo) in my testing of ProRes and I can gladly say it is the best thing Apple has done for Post Production since buying Key Grip from Macromedia….
FYI
all of these test are not just me making moral judgments I do not trust what my eyes tell me, I trust what the scopes tell me, that kind of hardware is less biased than I can be. So all of the tests were carried out with scopes and analytical tools to calibrate, process and monitor the images.gary adcock
Studio37
HD & Film Consultation
Post and Production WorkflowsInside look at the IoHD
https://library.creativecow.net/articles/adcock_gary/AJAIOHD.php