On (23/03/15 14:30), Ricardo Ribalda wrote: > With UVC 1.5 we get as little as one clock sample per frame. Which means > that it takes 32 frames to move from the software timestamp to the > hardware timestamp method. > > This results in abrupt changes in the timestamping after 32 frames (~1 > second), resulting in noticeable artifacts when used for encoding. > > With this patch we modify the update algorithm to work with whatever > amount of values are available. > > Tested-by: HungNien Chen <hn.chen@xxxxxxxxxxxxx> > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> Reviewed-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> > + * Have at least 1/4 of a second of timestamps before we > + * try to do any calculation. Otherwise we do not have enough > + * precision. This value was determined by running Android CTS > + * on different devices. > + * Dev_sof runs at 1KHz, and we have a fixed point precision of > + * 16 bits. > + */ > + if ((y2 - y1) < ( (1000 / 4) << 16)) A minor nit: extra space `( (` :)
