Hi,
Iñaki wrote:
I'm a student of the Informatic University of Madrid. I'm
delivering a processing motion pictures software in Linux. I need
low-latency field-rate capture and i've read in the video4linux list
all messages about this.
I only want to ask if finally it's possible to capture fields
instead of frames (obtaining a half time period to process) in
video4linux. I've studied video4linux files (videodev), system files
(ioctl.h, raw.c) and drivers files (bttv driver). The most similar
thing i've seen in v4l is the use of VBI device because v4l video
seems work only with frames.
For me your question isn't clear - why do you think, that capturing of
frames will be more CPU-costly unlike capturing of fields? Actually,
the capturing process is done by DMA-engine, without notable CPU's
eating (i hope, your code is enough optimised by compiler and fitted to
the CPU cache :-). The interval between fields also the same as between
frames - and you will have enough time for processing just half lines
from captured frames.
Regards,
Yurij
PS: the English isn't my native language, sorry :-)