MikeMouw
commented
10 years ago Email message from Ryan Lee on December 2: Kjell and I have completed our testing, and have arrived at a final video spec for the iPad presenter platform. We evaluated a wide range of frame sizes and data rates and tried to arrive at a happy medium that balances visual quality while remaining sensitive to network load and performance. We tested this both in MAT and in gallery. Here are our final specifications: h.264, 960x540, 23.97 fps, Progressive VBR 2-Pass, Target 1.25 Mbps, Max 1.5 Mbps AAC audio, 160kbps, 48khz, Stereo Square pixel AR (1.0) h.264 Profile: High, Level 3.1
Kjell mentioned an issue where certain videos do not play immediately, rather they take a moment to buffer and then require a second press of the 'play' icon. He is going to look into this, as it may have more to do with the quirks of embedded iPad video playback rather than a video data rate issue. Stay tuned for more info on this. We are in the process of re-exporting and replacing the videos in the app so that they are all consistent with these new specifications.
As always, please let me know if you encounter any issues, or have any questions!
kjell
Need to start video encode testing, using three video segments as a standard benchmark. Using one segment from Voices of the Communities, one segment from the Thematic videos, and one segment from a source outside of the MIA, need to run encoding tests to find the best balance between quick loading in the gallery and quality of the video on the iPad.
Need a log of variables to go with these encodes starting with the current MP4 and M4V .75 mbps files from Premiere that work, and the MP4 5 mbps files out of Premiere and Final Cut Pro that choked in Presenter.