I went through the workflow process to determine what caused the banding issue present in the Avengers Endgame IMAX trailer that I uploaded on Dec 21. From that, I was able to eliminate a transcoding step and now have a version that is much closer to the master. The original source was JPEG2000. In the first attempt, the original was transcoded to ProRes. The ProRes was then transcoded to H264. Some editing was performed on the H264 encode and the final video was produced from that. This new version used the ProRes created from the JPEG2000 source, and only one transcode to H264 was performed. Now, there is still some banding, but it is comparable to the original 1080p widescreen version. I don’t think I can get it any better.
You can get the new 4K version, as well as 1080p .mkv and .mp4 versions here. I have also experimented with H265 – HVEC, but I am not happy with the results. I will keep working on that, but for the mean time, I will stick with H264 – AVC.
In other news, I will also be uploading both Captain Marvel IMAX trailers, however I am going away to visit family so those will not arrive until the new year. With that I wish you a very happy remainder of 2018; and I look forward to providing you with the best quality trailers in 2019!