video - ffmpeg status & quality / cuda (CPU/GPU) -

video - ffmpeg status & quality / cuda (CPU/GPU) -

ffmpeg doing right?

so much time has passed since utilize ffmpeg convert clips on home web server, mp4 (h264 & aac) current overall standard (works on every console, smartphone, smarttv, pc) decided convert old clips various digital cameras to new container/codecs.

less space & same quality. compatibility support tags (subler mac)

after research opted ffmpeg because of various reasons

commandline (i made simple web interface default settings wich execute php's exec) the quality/size amount

i read many expensive video conversion softwares not able handle low bitrate videos properly. tested of them , not find proper export settings or not impressed results... had fixed default export setings, had lower video quality @ same filesize. ffmpeg allows me set -crf (18-24 usually) , -preset (veryslow, fast..) witch allows me cut down filesize drastically mantaining same visible quality.

said i'm using preset @ veryslow.(there placebo final video file 1% smaller in size).

and here command use

ffmpeg -y //overwrite file if exists -i inputfile // replace input file -metadata title=thetitle // set nice title, visible on modern devices -metadata date=thedate // set nice title, visible on modern devices -c:v libx264 // utilize h264 codec -crf 21 // seek different numbers between 18-26 -preset veryslow // placebo,slow,fast,ultrafast==big file -tune cinema // tune little -pix_fmt yuv420p // preferred on modern devices -profile:v main // preferred on modern devices -level 3.1 // preferred on modern devices -refs 4 // preferred on modern devices -c:a libfdk_aac // utilize aac -metadata:s:a language=eng // set language, visible on modern devices -b:a 128k // sound bitrate 128k mp3 192k -ar 48000 // 44100 ... whatever -ac 2 // audiochannels -movflags +faststart //move metadata in front end of video loads faster outputfile

some camcorder clips m2ts have avc/h264 compatible codec re-create stream. have ac3/dolby sorround audio. convert sound maintain ac3 sec sound track mapping ffmpeg streams.this allows me watch mp4 on browsers , mobile devices i'm able maintain surround sound playback on tv's, advanced media players or devices apple tv.

not i'm not happy speed (using quad core's) read 1 time again cuda opencl , there simple fact i'm not using other converters ffmpeg since alot of time.

is ffmpeg (with setting use) converter maintain same video quality source reducing space occupied , average of 30-40% ?

is gpu conversion bad (cuda .. testing gtx970)? nice add together more speed conversions using both gpu , cpu..but understanding cannot work together??? , using gpu drastical quality loss...cpu si more precise, gpu faster in calculation imprecise read.. expensive softwares utilize cuda preview purpose... right?

is ffmpeg or software compatible cpu+gpu encoding? don't remember where, read ffmpeg not videoconverter.

i'm happy size/quality, gained average of 30% in space no visible quality loss. parameters can adjust old analog videos deinterlaced in bad way.

maybe gain more size/quality software???

note: ffmpeg.it's free , has commandline can create own interface php html & js , utilize on various machines without need install in every device use. uplad idevice clips straight ffmpeg server.

btw.: explain downvotes...

edit:

@talonmies ...cuda tag removed :

http://www.nvidia.com/object/cuda_home_new.html

cuda® parallel computing platform , programming model invented nvidia. enables dramatic increases in computing performance harnessing powerfulness of graphics processing unit (gpu). millions of cuda-enabled gpus sold date, software developers, scientists , researchers finding broad-ranging uses gpu computing cuda. here few examples: - see more at: http://www.nvidia.com/object/cuda_home_new.html#sthash.deyaqae7.dpuf

isn't cuda programming model theoretical ffmpeg library should back upwards handle gpu encoding on nvidia cards gtx 970?? badaboom software http://www.geforce.com/games-applications/pc-applications/badaboom-media-converter.

is ffmpeg (with setting use) converter maintain same video quality source reducing space occupied , average of 30-40% ?

there many factors consider, broad generalization may able accomplish "visually lossless or nearly-so-but-most-users-can't-tell, not technically lossless" output smaller input. start ~-crf 18, increment until reach highest value still provides acceptable quality. utilize value rest of encoding.

if slow utilize faster -preset.

see ffmpeg wiki: h.264 video encoding guide more info.

is ffmpeg or software compatible cpu+gpu encoding?

ffmpeg supports nvenc. nvidia video coding sdk compile ffmpeg --enable-nonfree --enable-nvenc. slower x264 when providing similar quality, useful if cpu occupied.

x264 can back upwards opencl (--opencl option) lookahead, , maybe other stuff, may not worth using , slower. you'll have seek , compare; assuming have compatible hardware.

encoders claim utilize "(gp)gpu" in way slower and/or lower quality normal x264.

i read ffmpeg not videoconverter

without reasons given sounds unsubstantiated opinion.

video ffmpeg video-processing