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24-hour app #1: Die Schere, a video editor

I have long known that ap­pli­ca­tion de­vel­op­ment is an ar­du­ous process. I have al­so long sus­pect­ed one of the rea­sons it's ar­du­ous is the de­vel­op­er. I should be more speci­fic, I am one of the rea­son­s.

That's be­cause I don't know what I am do­ing, and I don't mean that in the "I am a lame pro­gram­mer" sense (even if that's al­so true some­what), but in the sense that I lit­er­al­ly don't know what the app should look like, or what its fea­ture set should be.

So, I have de­cid­ed to em­bark on a se­ries of ex­per­i­ments I will call 24-hour app­s.

Here are the rules:

  • I shall cre­ate a neat ap­­pli­­ca­­tion, sta­ble, use­­ful, us­able and de­­cen­t-look­ing.

  • I shall do it in no more than 24 hours. Af­ter that time, it should be at least good enough for a pre­view re­lease, if not a be­­ta.

  • Those 24 hours can be split in two or three ses­­sions

  • Time spent do­ing icon­s, doc­s, etc, counts.

  • All de­vel­op­­ment shall be pub­­lic (I am us­ing github)

  • I must have a use for the re­­sult­ing ap­­pli­­ca­­tion, and it should be at least an ad­e­quate so­lu­­tion for that prob­lem.

So, what's the first pro­jec­t? I call it Die Schere (The Scis­sors in ger­man) and it's a video ed­i­tor.

It's not a kden­live re­place­men­t, it's just the video ed­i­tor I wish I had when I need­ed to glue a piece of one video with a piece of an­oth­er.

In the old, pre-dig­i­tal world, that was done us­ing a cut­ter and scotch tape. I want Die Schere to be as use­ful and com­pre­hen­si­ble as that was, but use­ful for clum­sy peo­ple like my­self.

Here is a video af­ter to­day's ses­sion, which last­ed 8 hours:

The ba­sic func­tions are there, even if lots of work is still need­ed.

  • You can load clips to work with them

  • You can cut clips (like us­ing a cut­ter!)

  • You can choose the cut points in­­ter­ac­­tive­­ly or by ed­it­ing a time

  • You can ar­range them (like us­ing scotch tape!)

  • You can gen­er­ate the out­­put video

As a back­end it's us­ing men­coder, but there's no rea­son it should­n't work with ffm­peg or melt if some­one writes 20 lines of code.

Simple KDE Trick #2: using remote desktops with avahi, krfb and krdc

Most peo­ple nowa­days have more than one com­put­er. Of­ten, you are us­ing one, and would like to do some­thing in an­oth­er. In this video, I will ex­plain how triv­ial it is to do that with­out leav­ing your seat in a mod­ern Lin­ux us­ing KDE.

We will use the fol­low­ing:

  • Avahi, a ze­ro­­conf im­­ple­­men­­ta­­tion to let you find your com­put­ers in your net­­work with­­out wor­ry­ing about IP ad­­dress­es, DNS, etc.

  • kr­f­b, the KDE Re­­mote Frame Buf­fer. This is a pro­­gram to share your desk­­top over the net­­work.

  • krd­c, the KDE Re­­mote Desk­­top Clien­t, a VNC, RDP clien­t, which is what you use to see a desk­­top shared via kr­f­b.

I am sure users of oth­er op­er­at­ing sys­tems or desk­top en­vi­ron­ments will say they can do it just as eas­i­ly. In that case, feel free to do your own videos ;-)

Keep in mind that ac­cess­ing re­mote desk­tops over the in­ter­net is a whole dif­fer­ent beast, and this so­lu­tion is not meant for that case.

As usu­al, this video was record­ed us­ing qt-record­my­desk­top. There was mi­nor edit­ing us­ing men­coder.

The com­put­er used is the orig­i­nal Asus eee PC 701 4G, so you can see this is not ex­act­ly a hard­ware-in­ten­sive op­er­a­tion. I find the eee's small screen is great for this kind of ful­l-screen de­mo, be­cause it's not big enough to drown the im­por­tant part­s.

rst2pdf 0.12.2: minor bugfix release

I just up­load­ed rst2pdf 0.12.2 to http://rst2pdf.­google­code.­com Rst2pdf is a tool to gen­er­ate PDF files di­rect­ly from re­struc­tured text sources via re­port­lab.

This re­lease fix­es a ma­jor bug (in­com­pat­i­bil­i­ty with re­port­lab 2.1) as well as sev­er­al mi­nor ones and adds a mi­nor fea­ture (bet­ter styling of list item­s).

For more de­tail­s, you can see the changel­og

rst2pdf 0.12.1: minor bugfix release

I just up­load­ed rst2pdf 0.12.1 to http://rst2pdf.­google­code.­com

Rst2pdf is a tool to gen­er­ate PDF files di­rect­ly from re­struc­tured text sources via re­port­lab.

This re­lease has no new fea­tures, just a few bugs fixed.

For more in­for­ma­tion, see the changel­og


In an­oth­er rst2pdf-re­lat­ed note: some­one at the Uni­ver­si­tat Po­litec­ni­ca de Catalun­ya likes rst2pdf :-)


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