Hi, I'm new to Kdenlive and I've noticed that videos I render with H.264 and 1280x720 resolution actually come out as 1280x724 (according to mplayer), while other formats such as Xvid4 come out as 1280x720. Is this normal or have I got a problem somewhere?
I believe what you are seeing in mplayer is the scaled output resolution based on sample aspect ratio or some other factor. If so, that means there could be something wrong in the sample aspect ratio handling of MLT. Look further in the details of the mplayer output to see if you can locate where it says the coded resolution is and then later some info about filters being applied, etc.
What does 'ffmpeg -i the.mp4' say?
Also, what Kdenlive project setting did you use?
Well, this is strange - took me a little while to figure it out. Something in x264 (or ffmpeg's integration of it) enforces something when doing interlaced coding that caused the vertical resolution to change. Then, it adds 4 lines of bottom cropping in something called the H.264 VUI parameters, but not all decoders support this. MLT automatically uses interlaced coding when you use a Project setting that is not progressive. Merely changing the resolution in the Kdenlive render dialog does not change the progressive flag. Because you used a HD 1080i project setting, it was using interlaced coding. In the Kdenlive Render dialog, if you change the Scanning field to "Force Progressive" then you will get what you expect: 720.