Warp wrote:
>   mencoder is a tool from hackers to hackers.

In other words, hey, the guy who wrote it knows how to use it... :-)

It always bugs me when people build open-source tools they expect others 
to use (like libraries and such) and then expect you to read the source 
code to try to figure out what it does because they're too lazy to write 
even the vaguest of documentation.

For something like mencoder, it's pretty reasonable. Author needs to 
encode some video, author writes a tool, author gives it away.

But I run into way too many situations where people write stuff with the 
express intent of you using it and/or even improving it, and they don't 
put any documentation into it.  Imagine POV-Ray if it came with no 
documentation but the sample files....

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.

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>> Yes, but... does any program known to Man actually *play* MPEG-4?
> 
>> I'd use AVI, except that the AVI files Mencoder produces won't play 
>> properly.
> 
>   You are confusing the AVI format, which is a *container* format, with
> a video format, which for example MPEG4 is.

OK, I rephrase: I'd use fully uncompressed AVI, but when I ask Mencoder 
to do that, the result isn't playable with anything except MPlayer.

>   Most current players will play MPEG4 just fine if you have the proper
> codec installed, and a few will play it even if you don't (such as eg.
> vlcplayer).

OK, well if I ever see an MPEG4 file, I'll try it. ;-)

[I suppose I could ask Mencoder to make one - but then how would I know 
if it's really an MPEG4 file?]

>> MPEG-1 may be old and stuff, but it _works_ everywhere.
> 
>   At the cost of looking like crap or being humongous.

Well size isn't too much of an issue for me. Besides, the final image 
will be encoded with MPEG-2 anyway.

[Although actually... Mencoder is doing something strange at me. No 
matter how high I turn up the bitrate, the colours look a tad blocky for 
no apparent reason...]

>>>   mencoder is a tool from hackers to hackers.
> 
>> *sigh* Yes, from reading the "documentation" you do get that 
>> impression... :-(
> 
>   I see nothing wrong with the documentation. You just have to learn to
> read it.

You realise I've spent several *hours* today reading it trying to find 
the information I want, right?

>> Personally I think Virtual Dub is a fine tool, but I'm looking for 
>> something that can *programatically* build and play animations. 
> 
>   I don't understand what you mean by that.

Virtual Dub is nice, but you can only control it using a mouse. I want 
something I can control from the program I wrote.

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Darren New wrote:

> In other words, hey, the guy who wrote it knows how to use it... :-)

It always surprises me when a big well-known "jewl" of the open source 
scene has really poor documentation. You'd think something that popular 
would be well-documented...

It seems to be kinda pot luck though. Some open source still *is* 
fabulously documented. [The GIMP, MySQL, PostgreSQL off the top of my 
head.] And some things are shockingly UNdocumented. [I wouldn't say that 
Mencoder is *that* bad, but it could be much better.]

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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Orchid XP v8 wrote:
> OK, well if I ever see an MPEG4 file, I'll try it. ;-)

Isn't a VOB file on a DVD an mpeg4 file?

> [Although actually... Mencoder is doing something strange at me. No 
> matter how high I turn up the bitrate, the colours look a tad blocky for 
> no apparent reason...]

If the problem with Mencoder is B-frames, that would explain it.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.

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Orchid XP v8 wrote:
> It always surprises me when a big well-known "jewl" of the open source 
> scene has really poor documentation. You'd think something that popular 
> would be well-documented...

Yeah. Stuff like Freenet, which last I looked, was documented by people 
reading the source code and trying to figure out what it did well enough 
to write a user manual on how to use it. Like, WTF?

I personally can't imagine how you even start a major complicated 
project without writing some documentation first. "Hey, let's make this 
database engine, write all the code, then try to figure out what the 
layout in the files will be and what the API to access it should look 
like."  WTF?  At a minimum, put the notes you made while you were 
thinking about it on the wiki along with everything else.

-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.

Post a reply to this message

Darren New wrote:
> Orchid XP v8 wrote:
>> OK, well if I ever see an MPEG4 file, I'll try it. ;-)
> 
> Isn't a VOB file on a DVD an mpeg4 file?

	Nope. Mpeg2.

-- 
In an Astronomy class (toward an Astronomy major, not that gen-ed crap) 
the professor did not tell us we would have to remember constants, and 
he asked them as questions. They were short questions, and weren't worth 
a lot.

One of them was: What is the orbital period of Saturn? (2 pts/100)

I started thinking about Bode's law and the posibility I could calculate 
it from an approximate radius I would get from that law... if I could 
remember it. But when you expect a 72% to be an A on a test, you have 
bigger fish to fry.

Then I got it. It was right, it should work, and no one would have to be 
nailed to anything.

I wrote: One Saturn-Year

I didn't get credit for it. A couple years later a sophomore was telling 
me about this funny question he had in the same class. He showed it to 
me. It read:

What is the orbital period of Saturn? (Do not put one Saturn-Year)

I was so right that it had to be guarded against. Yet those were 2 
points I would never have.

(as told by SetupWeasel on Slashdot)


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

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Orchid XP v8 wrote:
>>     I think most people use ffmpeg for this kind of thing.
> 
> I don't have that. [Note that we're talking about M$ Windoze here.]

	Did you install the binary mplayer codecs package? It may have it.

Here's an old version for Windows:

http://www.videohelp.com/tools/ffmpeg

	Somehow, I feel there must be tools other than mencoder that will let 
you do this on Windows. I'm the wrong person to tell you them, though.


-- 
In an Astronomy class (toward an Astronomy major, not that gen-ed crap) 
the professor did not tell us we would have to remember constants, and 
he asked them as questions. They were short questions, and weren't worth 
a lot.

One of them was: What is the orbital period of Saturn? (2 pts/100)

I started thinking about Bode's law and the posibility I could calculate 
it from an approximate radius I would get from that law... if I could 
remember it. But when you expect a 72% to be an A on a test, you have 
bigger fish to fry.

Then I got it. It was right, it should work, and no one would have to be 
nailed to anything.

I wrote: One Saturn-Year

I didn't get credit for it. A couple years later a sophomore was telling 
me about this funny question he had in the same class. He showed it to 
me. It read:

What is the orbital period of Saturn? (Do not put one Saturn-Year)

I was so right that it had to be guarded against. Yet those were 2 
points I would never have.

(as told by SetupWeasel on Slashdot)


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

Post a reply to this message

Orchid XP v8 wrote:
> mencoder mf://*.png -ovc lavc -lavcopts vcodec=mpeg1video:vbitrate=5000 
> -ofps 12 -vf scale=720:576 -of lavf -lavfopts format=mpg -o out.mpg
> 
> (As a nice bonus, since it's compressed it doesn't take up my entire 
> harddrive! The bitrate shown seems to produce pretty good results.)
> 
> I'm curios... why is it so damned hard to do this??

	Why do you think it's hard.

-ovc is needed to specify the codec. You'd need this for any general 
purpose encoder.

-lavcopts specify the options for the lavc codec.

vcodec is to specify the format (they have mpeg2 if you want that instead).

vbitrate specifies the bitrate.

-ofps is the framerate - needed if you're not going to use the default.

-vf scale is because you wanted to scale.

-of is needed because it does avi by default. My mencoder has an mpeg 
option - but you chose lavf...

Most of these things will be needed whatever software you use. I've 
noticed converting to MPEG1 or 2 is always a pain - I just use the avi 
format and a codec like xvid. The commandline is a bit short.

-- 
In an Astronomy class (toward an Astronomy major, not that gen-ed crap) 
the professor did not tell us we would have to remember constants, and 
he asked them as questions. They were short questions, and weren't worth 
a lot.

One of them was: What is the orbital period of Saturn? (2 pts/100)

I started thinking about Bode's law and the posibility I could calculate 
it from an approximate radius I would get from that law... if I could 
remember it. But when you expect a 72% to be an A on a test, you have 
bigger fish to fry.

Then I got it. It was right, it should work, and no one would have to be 
nailed to anything.

I wrote: One Saturn-Year

I didn't get credit for it. A couple years later a sophomore was telling 
me about this funny question he had in the same class. He showed it to 
me. It read:

What is the orbital period of Saturn? (Do not put one Saturn-Year)

I was so right that it had to be guarded against. Yet those were 2 
points I would never have.

(as told by SetupWeasel on Slashdot)


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

Post a reply to this message

Warp wrote:
>   Nowadays you might want to use mpeg4 instead of mpeg1. The former can
> compress to less than one fourth the size of the latter, while retaining
> the same image quality (or even better).

	Many DVD players can't handle it. However, if that's not his target, 
I'll agree that mpeg1 is a bad idea. But then again, I get occasional 
requests from friends to encode stuff from one format to another because 
they want to send it to relatives, and they want to make sure it'll 
work. The assumptions are that they won't have special software like 
Quicktime Player or VLC, nor will they have any codecs that don't come 
with Windows. The only real option is MPEG1 or 2.

-- 
In an Astronomy class (toward an Astronomy major, not that gen-ed crap) 
the professor did not tell us we would have to remember constants, and 
he asked them as questions. They were short questions, and weren't worth 
a lot.

One of them was: What is the orbital period of Saturn? (2 pts/100)

I started thinking about Bode's law and the posibility I could calculate 
it from an approximate radius I would get from that law... if I could 
remember it. But when you expect a 72% to be an A on a test, you have 
bigger fish to fry.

Then I got it. It was right, it should work, and no one would have to be 
nailed to anything.

I wrote: One Saturn-Year

I didn't get credit for it. A couple years later a sophomore was telling 
me about this funny question he had in the same class. He showed it to 
me. It read:

What is the orbital period of Saturn? (Do not put one Saturn-Year)

I was so right that it had to be guarded against. Yet those were 2 
points I would never have.

(as told by SetupWeasel on Slashdot)


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

Post a reply to this message

Orchid XP v8 wrote:
> Mencoder/MPlayer can do this - although it seems to be horribly 
> difficult to get right. (E.g., I just discovered that the filename used 
> for the output file can actually affect the transcoding process - WTF?)

	I find this hard to believe - especially when you specify the format 
and codec.

-- 
In an Astronomy class (toward an Astronomy major, not that gen-ed crap) 
the professor did not tell us we would have to remember constants, and 
he asked them as questions. They were short questions, and weren't worth 
a lot.

One of them was: What is the orbital period of Saturn? (2 pts/100)

I started thinking about Bode's law and the posibility I could calculate 
it from an approximate radius I would get from that law... if I could 
remember it. But when you expect a 72% to be an A on a test, you have 
bigger fish to fry.

Then I got it. It was right, it should work, and no one would have to be 
nailed to anything.

I wrote: One Saturn-Year

I didn't get credit for it. A couple years later a sophomore was telling 
me about this funny question he had in the same class. He showed it to 
me. It read:

What is the orbital period of Saturn? (Do not put one Saturn-Year)

I was so right that it had to be guarded against. Yet those were 2 
points I would never have.

(as told by SetupWeasel on Slashdot)


                     /\  /\               /\  /
                    /  \/  \ u e e n     /  \/  a w a z
                        >>>>>>mue### [at] nawazorg<<<<<<
                                    anl

Post a reply to this message