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• Wildcard for sequential images

  16 septembre 2013, par abalter

  I'm trying to animate a series of jpg files using avconv. Based on numerous examples, I'm trying using %d.jpg to specify the files. Or %05d.jpg. However, I'm getting :

  avconv -i %d.jpg a.avi
  
  avconv version 0.8.3-4:0.8.3-0ubuntu0.12.04.1, Copyright (c) 2000-2012 the Libav developers built on Jun 12 2012 16:37:58 with gcc 4.6.3
  
  %d.jpg: No such file or directory

  Here is a snip of my directory listing :

  10380.jpg
  
  10390.jpg
  
  10400.jpg
  
  1040.jpg
  
  10410.jpg
  
  10420.jpg
  
  10430.jpg
  
  10440.jpg

  There are jpegs from 00000.jpg to 14400.jpg

  I don't really understand that wildcard system, but that is what is in examples.

  (note : I tagged it ffmpeg because a tag for avconv does not exist, and avconv supersedes ffmpeg)

  Update
  I'm updating the question based on the answer below by @av501.

  To begin with, I have a list of png files with sequential ordering by 10. They have text preceding a 5 digit integer. For example :

  SkinMattekNutrient_py_00000.png
  
  SkinMattekNutrient_py_00010.png
  
  SkinMattekNutrient_py_00020.png
  
  ...
  
  SkinMattekNutrient_py_10440.png

  What would be the way to batch convert these to jpg ? I tried

  convert ...
  
  SkinMattekNutrient_py_%05d.png %05d.jpg

  and

  convert ...
  
  SkinMattekNutrient_py_%5d.png %5d.jpg

  But I get :

  convert SkinMattekNutrient_py_%05d.png %05d.jpg
  
  convert: missing an image filename `%05d.jpg' @ error/convert.c/ConvertImageCommand/3011.

• ffmpeg duplicates first frame

  6 mars 2016, par user1605871

  When I create a video from series of images, it always duplicates the first frame several times, even when I choose a framerate, which is a multiple of the number of images. This is for a folder with 290 frames. Does anyone know how to fix this ? I’ve tried several things, for hours.

  Command is like this :

  $cmd5 = 'cat Folder/*.jpg | ffmpeg -f image2pipe -vcodec mjpeg -framerate 290/10 -i - -vcodec libx264 -vf \'scale=trunc(iw/2)*2:trunc(ih/2)*2\' Folder/out.mp4';

• Winamp and the March of GUI

  1er juillet 2012, par Multimedia Mike — General, ars technica, gui, user interface, winamp

  Ars Technica recently published a 15-year retrospective on the venerable Winamp multimedia player, prompting bouts of nostalgia and revelations of "Huh ? That program is still around ?" from many readers. I was among them.

  
  
  

  I remember first using Winamp in 1997. I remember finding a few of these new files called MP3s online and being able to play the first 20 seconds using the official Fraunhofer Windows player— full playback required the fully licensed version. Then I searched for another player and came up with Winamp. The first version I ever used was v1.05 in the summer of 1997. I remember checking the website often for updates and trying out every single one. I can’t imagine doing that nowadays— programs need to auto-update themselves (which Winamp probably does now ; I can’t recall the last time I used the program).

  Video Underdog
  The last time Winamp came up on my radar was early in 2003 when a new version came with support for a custom, proprietary multimedia audio/video format called Nullsoft Video (NSV). I remember the timeframe because the date is indicated in the earliest revision of my NSV spec document (back when I was maintaining such docs in a series of plaintext files). This was cobbled together from details I and others in the open source multimedia community sorted out from sample files. It was missing quite a few details, though.

  Then, Winamp founder Justin Frankel — introduced through a colleague on the xine team — emailed me his official NSV format and told me I was free to incorporate details into my document just as long as it wasn’t obvious that I had the official spec. This put me in an obnoxious position of trying to incorporate details which would have been very difficult to reverse engineer without the official doc. I think I coped with the situation by never really getting around to updating my doc in any meaningful way. Then, one day, the official spec was released to the world anyway, and it is now mirrored here at multimedia.cx.

  I don’t think the format ever really caught on in any meaningful way, so not a big deal. (Anytime I say that about a format, I always learn it saw huge adoption is some small but vocal community.)

  What’s Wrong With This Picture ?
  What I really wanted to discuss in this post was the matter of graphical user interfaces and how they have changed in the last 15 years.
  
  I still remember when I first downloaded Winamp v1.05 and tried it on my Windows machine at the time. Indignantly, the first thought I had was, "What makes this program think it’s so special that it’s allowed to violate the user interface conventions put forth by the rest of the desktop ?" All of the Windows programs followed a standard set of user interface patterns and had a consistent look and feel... and then Winamp came along and felt it could violate all those conventions.

  I guess I let the program get away with it because it was either that or only play 20-second clips from the unregistered Fraunhofer player. Though incredibly sterile by comparison, the Fraunhofer player, it should be noted, followed Windows UI guidelines to the letter.

  As the summer of 1997 progressed and more Winamp versions were released, eventually one came out (I think it was v1.6 or so) that supported skins. I was excited because there was a skin that made the program look like a proper Windows program— at least if you used the default Windows color scheme, and had all of your fonts a certain type and size.

  Skins were implemented by packaging together a set of BMP images to overlay on various UI elements. I immediately saw a number of shortcomings with this skinning approach. A big one was UI lock-in. Ironically, if you skin an app and wish to maintain backwards compatibility with the thousands of skins selflessly authored by your vibrant community (seriously, I couldn’t believe how prolific these things were), then you were effectively locked into the primary UI. Forget about adding a new button anywhere.

  Another big problem was resolution-independence. Basing your UI on static bitmaps doesn’t scale well with various resolutions. Winamp had its normal mode and it also had double-sized mode.

  Skins proliferated among many types of programs in the late 1990s. I always treasured this Suck.com (remember them ? that’s a whole other nostalgia trip) essay from April, 2000 entitled Skin Cancer. Still, Winamp was basically the standard, and the best, and I put away my righteous nerd rage and even dug through the vast troves of skins. I remember settling on Swankamp for a good part of 1998, probably due to the neo-swing revival at the time.

  
  
  

  Then again, if Winamp irked me, imagine my reaction when I was first exposed to the Sonique Music Player in 1998 :

  
  
  

  The New UI Order
  Upon reflection, I realize now that I had a really myopic view of what a computer GUI should be. I thought the GUIs were necessarily supposed to follow the WIMP (windows, icons, mouse, pointer) paradigm and couldn’t conceive of anything different. For a long time, I couldn’t envision a useful GUI on a small device (like a phone) because WIMP didn’t fit well on such a small interface (even though I saw various ill-fated attempts to make it work). This thinking seriously crippled me when I was trying to craft a GUI for a custom console media player I was developing as a hobby many years ago.

  I’m looking around at what I have open on my Windows 7 desktop right now. Google Chrome browser, Apple iTunes, Adobe Photoshop Elements, and VMware Player are 4 programs which all seem to have their own skins. Maybe Winamp doesn’t look so out of place these days.