optimal ffmpeg settings for screencast?

[yari]

what would be optimal setting for screencasts....one that would typically involve just a windows gui. would the resulting compression rates be economical ? with or without x264 ?

[Sharktooth]

optimal = best = not allowed here.

[Ranguvar]

optimal = best = not allowed here.

I disagree... optimal is a perfectly good question. Like if I asked what's optimal for anime. Optimal would probably be more refs, less merange, lower beta deblocking, higher alpha deblocking.

Anyways, OP, I would recommend off the top of my head that more refs will probably help a lot, probably p4x4 blocks will help more than usual, and it might be good to increase alpha deblocking for less mosquito noise and blocks / decrease beta deblocking for better retention of sharp lines. Also, try to keep a high resolution, preferably anamorphic. Other than that, experiment.

[Dark Shikari]

Anyways, OP, I would recommend off the top of my head that more refs will probably help a lot, probably p4x4 blocks will help more than usual, and it might be good to increase alpha deblocking for less mosquito noise and blocks / decrease beta deblocking for better retention of sharp lines. Also, try to keep a high resolution, preferably anamorphic. Other than that, experiment.I'd say that for screen capture (assuming its mostly basic Windows-style graphics, e.g. menus, buttons, etc):

1. No AQ, since everything is either "line" or "flat color".
2. Subpartitions probably aren't that useful--multiref might be useful.
3. A good motion search is likely very important if you're going to be moving around windows a lot.
4. Trellis is probably a good idea.

[yari]

thank you,

but i've no idea what those things mean or do....can someone link me to a general guide to all those stuff ?

[yari]

okay im reading this....its a start http://www.digital-digest.com/articles/x264_options_page2.html

[smok3]

yari: really depends on what kind of screencats it is, also depends on how pretty do you want it, i did this 'guide' few years ago, using vp6, not pretty, but readable imho (and i didn't bother with settings much);
http://somestuff.org/video_guides/all/flvplayer.php?moviename=movies/audacity_640_480.flv (mute)

a. this was captured with http://camstudio.org/
b. then avisynth for resizing, frame-rate changes
c. vp6 (while today you 'should' use x264 if target is flash)

[smok3]

i found the original avi clip, re-encoded by today's standards, again didn't bother with cmd much;

http://somestuff.org/flashAVC/flvplayer.php?moviename=movies/audacity-x800y600.mp4

(x264 --pass 1 --bitrate 480 --stats "" --bframes 1 --subme 1 --analyse none --me dia --progress --no-psnr --filter "0,0" --output NUL ""
x264 --pass 2 --bitrate 480 --stats "" --ref 5 --bframes 1 --subme 6 --b-rdo --analyse p8x8,b8x8,i4x4,p4x4 --progress --no-psnr --filter "0,0" --output "" "")

x264 thrown an error about converging the 1st pass curve, but still manages to get throught 2nd pass with incredibly low bitrate of 175 kbps.

[poisondeathray]

@smok3 -

1) Do you know offhand what x264 settings are compatible with streaming/embedding x264 in .mp4 with Flash Player or JW? Would it be similar to a Quicktime compatible setting?

2) I see you are using the JW media player; do you know of any differences in cmopatibility between JW and Adobe's player?

Sorry for hijacking the thread

[Dark Shikari]

@smok3 -

1) Do you know offhand what x264 settings are compatible with streaming/embedding x264 in .mp4 with Flash Player or JW? Would it be similar to a Quicktime compatible setting?There's basically no limit from what I've seen. Even totally maxed settings (http://mirror05.x264.nl/Dark/Flash/mof.html) seem to work fine.

2) I see you are using the JW media player; do you know of any differences in cmopatibility between JW and Adobe's player?

Sorry for hijacking the threadAdobe has a player?

[smok3]

1) (almost) anything goes, compatibility is much better than with quicktime
2) JW is using adobe flash to operate (one layer above the flash that is), what is the question?

[Dark Shikari]

thank you,

but i've no idea what those things mean or do....can someone link me to a general guide to all those stuff ?Read this page (http://ffmpeg.x264.googlepages.com/mapping) and this page (http://rob.opendot.cl/index.php/useful-stuff/ffmpeg-x264-encoding-guide/) and this page (http://rob.opendot.cl/index.php/useful-stuff/x264-to-ffmpeg-option-mapping/).

[yari]

yari: really depends on what kind of screencats it is, also depends on how pretty do you want it, i did this 'guide' few years ago, using vp6, not pretty, but readable imho (and i didn't bother with settings much);
http://somestuff.org/video_guides/all/flvplayer.php?moviename=movies/audacity_640_480.flv (mute)

a. this was captured with http://camstudio.org/
b. then avisynth for resizing, frame-rate changes
c. vp6 (while today you 'should' use x264 if target is flash)

that is sort of the idea....but im wondering whether the resulting storage size is signficantly reduced for such videos ? would it be possible to make the size of the video much bigger and still have "readable" quality ?

thank you.

[yari]

Read this page (http://ffmpeg.x264.googlepages.com/mapping) and this page (http://rob.opendot.cl/index.php/useful-stuff/ffmpeg-x264-encoding-guide/) and this page (http://rob.opendot.cl/index.php/useful-stuff/x264-to-ffmpeg-option-mapping/).

thanks!

[smok3]

would it be possible to make the size of the video much bigger and still have "readable" quality ?

yes (you did see my other link?)

[yari]

yes (you did see my other link?)

ah i missed that one. thank you.

this is bloody amazing quality! what was the original video size?

i see that 640x480 is around 1.5mb.

i wonder how big the 800 is....

if i were to not use x264 library, how much can i expect?

i did a quick experiment but i found that using x264, although cpu intensive (fan was making lot of noise) and taking longer to encode, it resulted in superioir quality and 20%~30% smaller file size compared to just encoding to flv in ffmpeg. is this like for any type of videos out there ?

[Comatose]

(my opinion) x264 is the most efficient H.264 encoder right now, and H.264 is the most efficient widely used codec right now, so yes :p

[Dark Shikari]

ah i missed that one. thank you.

this is bloody amazing quality! what was the original video size?

i see that 640x480 is around 1.5mb.

i wonder how big the 800 is....

if i were to not use x264 library, how much can i expect?

i did a quick experiment but i found that using x264, although cpu intensive (fan was making lot of noise) and taking longer to encode, it resulted in superioir quality and 20%~30% smaller file size compared to just encoding to flv in ffmpeg. is this like for any type of videos out there ?H.264 is already by a wide margin the most efficient format you can encode to with ffmpeg--and x264 is one of the best H.264 encoders out there (if not the best, for many applications)--so expect a rather large advantage from using it ;)