How to convert back QImage to cv::Mat?

CAN I CONVERT AN HD VIDEO FROM .MOV TO .AVI (WHICH IS STANDARD DEF.) AND THEN BACK TO .MOV (HD AGAIN) ?

• will thej quality go back to normal??? PLEASE dont advertise your converter here! i am not asking for a converter suggestion! i'm asking if the video will still be HD after converting .mov to .avi and then back to .mov original video is HD in .mov but in order to edit it i would convert to .avi and when its done being editted convert it back to .mov

• Answer:

  No. The video resolution can only be as good as the lowest resolution it gets rendered to. When high definition is downsampled to standard definition, then standard definition is the highest quality it will ever be - unless you back to the original high definition video file. If the video is a high definition h.264 format in a MOV "envelope", you can transcode it ti a h.264 high definition format in a AVI "envelope". If you downsample the h.264 high definition MOV files to a standard definition AVI file, all the high definition information is discarded. In video, the resolution of that video is defined by the number of horizontal rows that make up the video. Standard definition video is 480 horizontal lines. anything above this - for consumer camcorders - is usually 720 or 1080 horizontal lines of resolution. Anything less than 480 horizontal lines is less than standard def video. Lets say your video starts as a 1080i, h.264, HDV format video. It gets downsampled to 480 horizontal line standard def NTSC video. You *could* save that standard def file as a h.264 HDV file - but the video resolution won't magically get the discarded horizontal lines to make to back to 1080. Whether that video is in a MOV or AVI envelope dies not matter. MOV files can be high definition, standard definition or less than standard definition. Same with AVI files.