_Gyan_

11 ms·

61.
by _Gyan_ 7y ago
There is no provision for partial stream encoding. It's either complete streamcopy or encoding.
62.
by _Gyan_ 7y ago
" -f lavfi -i testsrc - declaration of an input. The input format is lavfi, the input file is testsrc. This is duplicated four times to imitate four different inputs. " You can feed a single input multiple times in a filtergraph,
63.
by _Gyan_ 7y ago
You've missed all the component options :) See https://ffmpeg.org/ffmpeg-all.html
64.
by _Gyan_ 7y ago
Filtergraph declarations in files* can have whitespace so you can format it logically. Each option of a filter can be on different lines, if you like. *via shell too, if the arg is quoted/escaped.
65.
by _Gyan_ 7y ago
You also have a processing graph for the intermediate filters. So ideally you want graph nodes represented by some identifier which can then be referenced by other nodes. Unless I misunderstand you, this is already the case. Simple or com
66.
by _Gyan_ 7y ago
The CLI syntax design reflects the N-inputs --> N-outputs capability and no. of options reflects the number of components e.g. there are 300+ demuxers and 400+ filters available. This is not to say there isn't scope for improvement.
67.
by _Gyan_ 7y ago
the fps filter (which gets auto-inserted with -r) Which ffmpeg version are you using? This hasn't been the case since 2012. Both input and output -r are effected through fftools and not libs.
68.
by _Gyan_ 7y ago
See https://superuser.com/questions/1270950 for a way to do it without needing to create a masking image.
69.
by _Gyan_ 7y ago
I tend to think the person who can truly identify that the question is a dupe is the questioner. Not IME. It depends on whether the Q is a XY problem or if the asker is acquainted with the problem-domain. I engage with Qs on the use of a
70.
by _Gyan_ 7y ago
See https://wiki.multimedia.cx/index.php/PCM#DVD_PCM
71.
by _Gyan_ 7y ago
> not enough information to mux an H.264 stream. The parser is inserted after demux and before decode . Yes, xPS are also located and decoded. My comment wasn't meant to be an enumeration. Specific tasks depend on the complexity
72.
by _Gyan_ 7y ago
Parsers typically are used to correctly demarcate packet boundaries in (coded) bitstreams e.g. H.264 bitstream is partitioned into NAL units and the parser assembles all relevant units for a single frame/slice so that the decoder gets
73.
by _Gyan_ 7y ago
PCM-DVD has a specific way in how the channels are interleaved. For bit depths higher than 16, each sample is split so that the lowest byte is stored following the high bytes of all channels. There's also a 3-byte metadata which has to
74.
FFmpeg 4.2(ffmpeg.org)
327 points by _Gyan_ 7y ago|79 comments
75.
by _Gyan_ 7y ago
Just try copying video between different containers (mkv, ts, avi for one) without reencoding. I do, all the time. AVI is an old container and it has issues with B-frames and also VFR but those are container limitations, not a libavformat
76.
by _Gyan_ 7y ago
libavformat is rather difficult to use and difficult to fix bugs in - you'll never find the bugs. Some examples? encoding never worked as well, which is why nobody uses ffmpeg2/4/etc and x264 is a separate project. Most u
77.
by _Gyan_ 7y ago
I'll be adding entries for all the missing demuxers/decoders/encoders/muxers eventually . At present, only a fraction have been documented.
78.
by _Gyan_ 7y ago
No, limited range is the most common and expected range for YUV videos. Many players don't look or respect the container metadata such as nclx in MP4 or the bitstream VUI flags and assume limited range.
79.
by _Gyan_ 7y ago
Just a parenthetical note: The article, in its ffmpeg encoding guide says, -f - Only used in the first pass. Specifies the format of the output file in the second pass i.e. MP4 in this case This is not required to be the same as the
80.
by _Gyan_ 8y ago
What does this mean? Once you've a decoded 10-bit raster, what's the limitation you're encountering?
81.
by _Gyan_ 8y ago
Handbrake applies about a dozen patches on top of the FFmpeg tree. See them at https://github.com/HandBrake/HandBrake/tree/master/contrib/f... Note that HB uses a release (4.1) rather than git maste
82.
by _Gyan_ 8y ago
Linked earlier at https://news.ycombinator.com/item?id=18518302
83.
by _Gyan_ 8y ago
https://codereview.stackexchange.com/
84.
by _Gyan_ 8y ago
Appears that two-way comms was required for Beidou-1, not BeiDou-2. See https://space.stackexchange.com/questions/30839/is-two-way-c...