Ivan Myles
Forum Replies Created
-
Try using the Time Warp effect in AE to generate the extra frames for playing at 40% speed in a 24p sequence.
-
What version of Creative Suite are you using?
Did you apply any effects in Premiere Pro? If so, what was the bit depth of the effects?
After enabling Maximum Bit Depth in the Premiere Pro sequence settings, save the project. Close and reopen the AE project to update the link.
What bit depth are the AE project and AE effect(s)? Is there a color space applied to the AE project?
As a comparison, try exporting a short test file from Premiere Pro as a DPX image sequence with the export settings at 48-bit Depth and Maximum Bit Depth enabled. Import to AE and apply the same effects in a 16- or 32-bit project.
Export a test file from the 16- or 32-bit AE project using a DPX image sequence with Billions of Colors enabled. Import the test file to Premiere Pro, create a sequence from the imported file, and enable Maximum Bit Depth in the sequence settings. View the sequence in the YC scope and RGB Parade to verify whether there and any gaps in the luma and RGB curves.
-
Please post the export settings. How long is the video?
-
Apply the Fast Color Corrector or Levels effect and keyframe the white and black levels. Reference the YC Scope and maintain a steady luma profile through the clip.
-
You would be better off preparing the footage. 60i is equivalent to 30p once converted from interlaced to progressive. Playing at 40% speed requires construction of new frames. Do you have access to After Effects?
-
On Windows consider using AVC-Intra or installing Cineform GoPro. Uncompressed is another option (V210, DPX, QuickTime YUV) but it will create very large files.
-
1. In the original post you used the qualifier, “.. good enough for the average person to notice.” That’s difficult to determine.
2. A sequence of short clips (at the extreme, a series of discontinuous photos like this) requires higher bitrate because a larger percentage of the file is I-frames (which are full images) versus P- and B-frames (which are constructed from other frames and therefore much smaller). At the other extreme, a sequence several minutes long of a single static photo could be encoded at a lower bitrate.
Yes, that’s the calculation:
Mbps = Width x Height x FPS x bpp / 1024 / 1024 -
There are a lot of qualifiers that make it difficult to answer your question: codec, display size, average person, amount of motion, length of clips… As a general guideline for H.264 I find that 0.35-0.40 bits/pixel is reasonably close to blu-ray quality (0.65-0.80 bpp) when encoded with 2-pass VBR, a key frame distance of 10-15 frames; and viewed on a computer screen or smaller. Depending on the circumstance one could argue that the rate should either be doubled to Blu-ray quality or cut in half.
-
At high bitrates (0.65-0.80 bits per pixel) the two codecs produce similar results. However, MPEG-2 (H.262) is older; H.264 includes newer compression technologies designed to retain better visual quality at low bitrates whereas MPEG-2 deteriorates more quickly. For example, YouTube H.264 videos are typically encoded at about 0.07 bpp.
There are other considerations, also. H.264 is ubiquitous and therefore videos can be shared more easily. In addition, the H.264 licensing terms allow free distribution of videos 12 minutes or shorter, but MPEG-2 requires a royalty fee.
At this point in time MPEG-2 is used primarily for DVDs; otherwise, H.264 is the more common choice.
-
I think QuickTime 32-bit processing is slowing you down (as others have mentioned), and the data storage system is a bottleneck during uploads (likely the SATA II data flow). To improve uploads you could distribute the source files across both RAID arrays and get a dedicated SSD for the cache files. Also, upgrading the system SSD might help depending on its excess capacity and performance. Empty the cache before opening the project, too.