Video Compression (Android)
Only devices with Android 4.1+ are able to do video compression in Telegram. It is related with the resolution of the video that is sent too. It has to be bigger than 640px in width or height. It's disabled for some devices too because some Androids (4.1 and 4.2) don't have a public API for video encoding.
Conditions to trim a video
- Audio codec = mp4a
- Video codec = supported by the device
- Any side of the video more than 640px OR if a side is less than 640px but video codec is h264
Conditions to compress a video
- Any side of the video over 640px
- Audio codec = mp4a
- A video encoder different than: OMX.google.h264.encoder / OMX.ST.VFM.H264Enc / OMX.Exynos.avc.enc / OMX.MARVELL.VIDEO.HW.CODA7542ENCODER / OMX.MARVELL.VIDEO.H264ENCODER
Green bar in compressed videos on Android 4.3 (older devices)
Some Android devices could compress videos like this:
It's an Android problem (means that device vendor didn't pass CTS and released the device without checking. On Android 4.3+ it can't be fixed by the Telegram Android developer anymore because on these Android versions Telegram is using only the Android API for conversion.