FFMPEG An Intermediate Guide/Flags
This should help define the flags command in FFMPEG.
The flag command is used to by calling "-flag", followed by a single space and then all flags with a plus "+" or minus "-" sign preceding each indicating active or inactive flag respectively.
mv4
[edit | edit source]Affects: Encoding, Video
use four motion vector by macroblock (mpeg4)
obmc
[edit | edit source]Affects: Encoding, Video
use overlapped block motion compensation (h263+)
qpel
[edit | edit source]Affects: Encoding, Video
use 1/4 pel motion compensation
loop
[edit | edit source]Affects: Encoding, Video
use loop filter
gmc
[edit | edit source]Affects: Encoding, Video
use gmc
mv0
[edit | edit source]Affects: Encoding, Video
always try a mb with mv=<0,0>
part
[edit | edit source]Affects: Encoding, Video
use data partitioning
gray
[edit | edit source]Affects: Encoding, Decoding, Video
only decode/encode grayscale
psnr
[edit | edit source]Affects: Encoding, Video
error[?] variables will be set during encoding
naq
[edit | edit source]Affects: Encoding, Video
normalize adaptive quantization
low_delay
[edit | edit source]Affects: Encoding, Video
force low delay
alt (deprecated)
[edit | edit source]Affects: Encoding, Video
alt used to be flag, but moved was to be a private option (named alternate_scan) for the mpeg2video and MPEG4 encoders.
enable alternate scantable (mpeg2/mpeg4)
global_header
[edit | edit source]Affects: Encoding, Video, Audio
place global headers in extradata instead of every keyframe
bitexact
[edit | edit source]Affects: Encoding, Decoding, Video, Audio, S (not sure but assuming subtitles)
EDVAS use only bitexact stuff (except (i)dct)
aic
[edit | edit source]Affects: Encoding, Video
h263 advanced intra coding / mpeg4 ac prediction
umv
[edit | edit source]Affects: Encoding, Video
use unlimited motion vectors
umv is no longer a flag option
cbp
[edit | edit source]Affects: Encoding, Video
use rate distortion optimization for cbp
qprd
[edit | edit source]Affects: Encoding, Video
use rate distortion optimization for qp selection
aiv
[edit | edit source]Affects: Encoding, Video
h263 alternative inter vlc
slice
[edit | edit source]Affects: Encoding, Video
slice is no longer a flag option
ilme
[edit | edit source]Affects: Encoding, Video Codecs/Containers: MPEG 2 and MPEG 4. Interlaced fotage
Force InterLaced Motion Estimation, this is only necessary if you are working with interlaced video. It will force FFMPEG to maintain Quality with interlace footage. If you wish to deinterlace your footage please use '-deinterlace' option, but this will cause a quality lose in the video. Rule of thumb is anything intended is for television is interlace, any other delivery format is most likely progressive.
ildct
[edit | edit source]Affects: Encoding, Video
Use when encoding Interlaced footage to ensure that FFMPEG doesn't field merge your DCT. Only affects Interlaced footage.
scan_offset
[edit | edit source]Affects: Encoding, Video
will reserve space for svcd scan offset user data
cgop
[edit | edit source]Affects: Encoding, Video
closed gop
Problems
[edit | edit source]trell
[edit | edit source]Trell is no longer a flag option, please use -trellis instead.