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• create short movie from images and save into mp4 or 3gp format android

  6 juin 2014, par new Project

  I want to make short movie clip from several images. I google very much but got only one answer that to use FFMPEG

  I have tried to compile that native library from ndk-r8 using cygwin in windows 7 but nothing happens and shows compile error.

  I have also try to compile and run github projects github.com/guardianproject/android-ffmpeg and github.com/appunite/AndroidFFmpeg but it also unsucessful.

  when i’ve read projects descriptions then someone told that its only working in linux or mac but i think its not the problem beacause i am using cygwin that used for linux on windows.

  In compiling i’ve got errors like prebuild library not found and something files not found.

  Is there any solution by someone or have compiled library that helps me a lot. Please suggest me some working tutorial or example that saves my lots of days.

  Thanks,.

• NAB 2010 wrapup

  15 avril 2010

  Another year of NAB has come and gone. Making it out of Vegas with some remaining faith in humanity seems like a successful outcome. So, anything worth talking about at the show ?

  First off, there’s 3d. 3D is The Next Big Thing, and that was obvious to anyone who spent half a second on the show floor. Everything from camera rigs, to post production apps, to display technology was all 3d, all the time. I’m not a huge fan of 3d in most cases, but the industry is at least feigning interest.

  Luckily, at a show as big as NAB, there’s plenty of other cool stuff to see. So, what struck my fancy ?

  First off, Avid and Adobe were showing new versions of Media Composer and Premiere. Both sounded pretty amazing on paper, but I must say I was somewhat underwhelmed by both in reality. Premiere felt a little rough around the edges - the Mercurial Engine wasn’t the sort of next generation tech that I expected. Media Composer 5 has some nice new tweaks, but it’s still rather Avid-y - which is good for Avid people, less interesting for the rest of us.

  In other software news, Blackmagic Design was showing off some of what they’re doing with the DaVinci technology that they acquired. Software-only Da Vinci Resolve for $999 is a pretty amazing deal, and the demos were quite nice. That said, color correction is an art, so just making the technology cheaper isn’t necessarily going to dramatically change the number of folks who do it well - see Color.

  Blackmagic also has a pile of new USB 3.0 hardware devices, including the absolutely gorgeous UltraStudio Pro. Makes me pine for USB 3.0 on the mac.

  On the production side, we saw new cameras from just about everyone. To start at the high end, the Arri Alexa was absolutely stunning. Perhaps the nicest digital cinema footage I’ve seen. Not only that, but they’ve worked out a usable workflow, recording to ProRes plus RAW. At the price point they’re promising, the world is going to get a lot more difficult for RED.

  Sony’s new XDCam EX gear is another good step forward for that format. Nothing groundbreaking, but another nice progression. I was kind of hoping we’d see 4:2:2 EX gear from them, but I suppose they need to justify the disc based formats for a while longer.

  The Panasonic AG-AF100 is another interesting camera, bringing micro 4/3rds into video. The only strange thing is the recording side - AVCHD to SD cards. While I’m thrilled to see them using SD instead of P2, it sure would have been nice to have an AVCIntra option.

  Finally, Canon’s 4:2:2 XF cams are a nice option for the ENG/EFP market. Nothing groundbreaking, aside from the extra color sampling, but it’s a nice step up from what they’ve been doing.

  Speaking of Canon, it’s interesting to see the ways that the 5d and 7d have made their way into mainstream filmmaking. At one point, I thought they’d be relegated to the indie community - folks looking for nice DoF on a budget. Instead, they seem to have been adopted by a huge range of productions, from episodic TV to features. While they’re not right for everyone, the price and quality make them an easy choice in many cases.

  One of the stars of the show for me was the GoPro, a small waterproof HD camera that ships with a variety of mounts, designed to be used in places where you couldn’t or wouldn’t use a more full featured camera. No LCD, just a record button and a wide angle lens. I bought two.

  Those are the things that stand out for me. While there was plenty of interesting stuff to be seen, given the current economic conditions at the University, I wasn’t exactly in a shopping mindset. The show definitely felt more optimistic than it did last year, and companies are again pushing out new products. However, attendances was about 20% lower than 2008, and that was definitely noticeable on the show floor.

• VP8 And FFmpeg

  18 juin 2010, par Multimedia Mike — VP8

  UPDATE, 2010-06-17 : You don’t need to struggle through these instructions anymore. libvpx 0.9.1 and FFmpeg 0.6 work together much better. Please see this post for simple instructions on getting up and running quickly.

  Let’s take the VP8 source code (in Google’s new libvpx library) for a spin ; get it to compile and hook it up to FFmpeg. I am hesitant to publish specific instructions for building in the somewhat hackish manner available on day 1 (download FFmpeg at a certain revision and apply a patch) since that kind of post has a tendency to rise in Google rankings. I will just need to remember to update this post after the library patches are applied to the official FFmpeg tree.

  Statement of libvpx’s Relationship to FFmpeg
  I don’t necessarily speak officially for FFmpeg. But I’ve been with the project long enough to explain how certain things work.

  Certainly, some may wonder if FFmpeg will incorporate Google’s newly open sourced libvpx library into FFmpeg. In the near term, FFmpeg will support encoding and decoding VP8 via external library as it does with a number of other libraries (most popularly, libx264). FFmpeg will not adopt the code for its own codebase, even if the license may allow it. That just isn’t how the FFmpeg crew rolls.

  In the longer term, expect the FFmpeg project to develop an independent, interoperable implementation of the VP8 decoder. Sometime after that, there may also be an independent VP8 encoder as well.

  Building libvpx
  Download and build libvpx. This is a basic ’configure && make’ process. The build process creates a static library, a bunch of header files, and 14 utilities. A bunch of these utilities operate on a file format called IVF which is apparently a simple transport method for VP8. I have recorded the file format on the wiki.

  We could use a decoder for this in the FFmpeg code base for testing VP8 in the future. Who’s game ? Just as I was proofreading this post, I saw that David Conrad has sent an IVF demuxer to the ffmpeg-devel list.

  There doesn’t seem to be a ’make install’ step for the library. Instead, go into the overly long directory (on my system, this is generated as vpx-vp8-nopost-nodocs-generic-gnu-v0.9.0), copy the contents of include/ to /usr/local/include and the static library in lib/ to /usr/local/lib .

  Building FFmpeg with libvpx
  Download FFmpeg source code at the revision specified or take your chances with the latest version (as I did). Download and apply provided patches. This part hurts since there is one diff per file. Most of them applied for me.

  Configure FFmpeg with 'configure --enable-libvpx_vp8 --enable-pthreads'. Ideally, this should yield no complaints and ’libvpx_vp8’ should show up in the enabled decoders and encoders sections. The library apparently relies on threading which is why '--enable-pthreads' is necessary. After I did this, I was able to create a new webm/VP8/Vorbis file simply with :

   ffmpeg -i input_file output_file.webm
  

  Unfortunately, I can’t complete the round trip as decoding doesn’t seem to work. Passing the generated .webm file back into FFmpeg results in a bunch of errors of this format :

  [libvpx_vp8 @ 0x8c4ab20]v0.9.0
  [libvpx_vp8 @ 0x8c4ab20]Failed to initialize decoder : Codec does not implement requested capability
  

  Maybe this is the FFmpeg revision mismatch biting me.

  FFmpeg Presets
  FFmpeg features support for preset files which contain collections of tuning options to be loaded into the program. Google provided some presets along with their FFmpeg patches :

  • 1080p50
  • 1080p
  • 360p
  • 720p50
  • 720p

  To invoke one of these (assuming the program has been installed via ’make install’ so that the presets are in the right place) :

   ffmpeg -i input_file -vcodec libvpx_vp8 -vpre 720p output_file.webm
  

  This will use a set of parameters that are known to do well when encoding a 720p video.

  Code Paths
  One of goals with this post was to visualize a call graph after I got the decoder hooked up to FFmpeg. Fortunately, this recon is greatly simplified by libvpx’s simple_decoder utility. Steps :

  • Build libvpx with --enable-gprof
  • Run simple_decoder on an IVF file
  • Get the pl_from_gprof.pl and dot_from_pl.pl scripts frome Graphviz’s gprof filters
  • gprof simple_decoder | ./pl_from_gprof.pl | ./dot_from_pl.pl > 001.dot
  • Remove the 2 [graph] and 1 [node] modifiers from the dot file (they only make the resulting graph very hard to read)
  • dot -Tpng 001.dot > 001.png

  Here are call graphs generated from decoding test vectors 001 and 017.

  
  

  

  Like this, only much larger and scarier (click for full graph)

  
  

  It’s funny to see several functions calling an empty bubble. Probably nothing to worry about. More interesting is the fact that a lot of function_c() functions are called. The ’_c’ at the end is important— that generally indicates that there are (or could be) SIMD-optimized versions. I know this codebase has plenty of assembly. All of the x86 ASM files appear to be written such that they could be compiled with NASM.

  Leftovers
  One interesting item in the code was vpx_scale/leapster. Is this in reference to the Leapster handheld educational gaming unit ? Based on this item from 2005 (archive.org copy), some Leapster titles probably used VP6. This reminds me of finding references to the PlayStation in Duck/On2’s original VpVision source release. I don’t know of any PlayStation games that used Duck’s original codecs but with thousands to choose from, it’s possible that we may find a few some day.