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• ARM compiler update

  15 janvier 2010, par Mans — ARM, Compilers

  Since my last shootout, all the tested vendors have updated their compilers. Here is a quick update on each of them.

  Both the 4.3 and 4.4 branches of FSF GCC have had bugfix releases, bringing them to 4.3.4 and 4.4.2, respectively. Neither update contains anything particularly noteworthy.

  The CodeSourcery 2009q3 release sees an update to a GCC 4.4 base, a significant change from the 4.3 base used in 2009q1. The update is a mixed blessing. In fact, it is mostly a curse and hardly a blessing at all. On the bright side, the floating-point speed regressions in 2009q1 are gone, 2009q3 being a few per cent faster even than 2007q3. Unfortunately, this improvement is completely overshadowed by a major speed regression on integer code, a whopping 24% in one case. This ties in with the slowdown previously observed with FSF GCC 4.4 compared to 4.3.

  ARM RVCT 4.0 is now at Build 697. This update fixes some bugs and introduces others. Notably, it no longer builds FFmpeg correctly. The issue has been reported to ARM.

  Texas Instruments, finally, have made a formal release, v4.6.1, of their TMS470 compiler incorporating various fixes allowing it to build a moderately patched FFmpeg. The performance remains somewhere between GCC and RVCT on average.

  In light of the above, my recommendations remain unchanged :

  • For a free compiler, choose CodeSourcery 2009q1. It beats GCC 4.3.4 by 5-10% in most cases.
  • GNU purists are best served by GCC 4.3.4, which is up to 20% faster than 4.4.2 and rarely slower.
  • When price is not a concern, ARM RCVT is a good option, outperforming GCC by up to a factor 2.
  • In all cases, disable any auto-vectorisation features.

  Regardless of which compiler is chosen, I cannot overstress the importance of testing. All compilers are crawling with bugs, and even the most innocent-looking code change can trigger one of them. When using a compiler other than GCC, extra caution is advised considering a lot of code is developed using only GCC and may thus fall prey to bugs unique to said other compiler.

• JavaCV RedHat Linux 6.6 x64 NoClassDefFound : Could not initialize class org.bytedeco.javacpp.avutil

  28 novembre 2015, par ChrisGeo

  I want to run a simple .flv to .mp4 conversion on a Linux machine

  Till now I was including the following dependencies and it was working fine on Ubuntu 12.x and CentOS

  <dependency>
  
     <groupid>org.bytedeco.javacpp-presets</groupid>
  
     <artifactid>ffmpeg</artifactid>
  
     <version>2.7.1-1.0</version>
  
     <classifier>linux-x86_64</classifier>
  
  </dependency>

  Red Hat uname -a

  x86_64 #1 SMP Tue Sep 16 01:56:35 EDT 2014 x86_64 x86_64 x86_64 GNU/Linux
  
  
  
  Red Hat lsb_release -a
  
  LSB Version:    :base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch
  
  Distributor ID: RedHatEnterpriseServer
  
  Description:    Red Hat Enterprise Linux Server release 6.6 (Santiago)
  
  Release:        6.6
  
  Codename:       Santiago

  CentOS uname -a

  .x86_64 #1 SMP Tue Nov 3 19:10:07 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

  However when trying it in RedHat Linux I get the following exceptions

  Application startup failed

  java.lang.NoClassDefFoundError: Could not initialize class org.bytedeco.javacpp.avutil
  
      at java.lang.Class.forName0(Native Method)
  
      at java.lang.Class.forName(Class.java:270)
  
      at org.bytedeco.javacpp.Loader.load(Loader.java:390)
  
      at org.bytedeco.javacpp.Loader.load(Loader.java:358)
  
      at org.bytedeco.javacpp.avformat$AVFormatContext.<clinit>(avformat.java:2539)
  
      at org.bytedeco.javacv.FFmpegFrameGrabber.startUnsafe(FFmpegFrameGrabber.java:383)
  
      at org.bytedeco.javacv.FFmpegFrameGrabber.start(FFmpegFrameGrabber.java:377)
  
      at com.example.Application.convert(Application.java:53)
  
      at com.example.Application.run(Application.java:103)
  
      at org.springframework.boot.SpringApplication.runCommandLineRunners(SpringApplication.java:674)
  
      at org.springframework.boot.SpringApplication.afterRefresh(SpringApplication.java:693)
  
      at org.springframework.boot.SpringApplication.run(SpringApplication.java:322)
  
      at org.springframework.boot.SpringApplication.run(SpringApplication.java:969)
  
      at org.springframework.boot.SpringApplication.run(SpringApplication.java:958)
  
      at com.example.Application.main(Application.java:28)
  
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
  
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  
      at java.lang.reflect.Method.invoke(Method.java:606)
  
      at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:53)
  
      at java.lang.Thread.run(Thread.java:745)
  
  </clinit>

  I tried with 32 bit version :

  <dependency>
  
     <groupid>org.bytedeco.javacpp-presets</groupid>
  
     <artifactid>ffmpeg</artifactid>
  
     <version>2.7.1-1.0</version>
  
     <classifier>linux-x86</classifier>
  
  </dependency>

  Same result.

  Then I tried with simply

  org.bytedeco
  javacv
  1.0

  and mvn package -Dplatform.dependencies=true so I got ALL dependencies.

  Still the same. Any one have an idea what I’m doing wrong ?

• Is it possible to merge multiple FFMPEG commands (cuts, slow down, watermark) into one in order to increase performance ?

  14 novembre 2022, par Nectarie PF

  I wrote a small piece of software in PHP, using FFMPEG commands via shell exec. The final purpose is to take a 7 seconds MP4 file from a GoPro and transform it in order to achieve a sort of boomerang effect :

  


  

  • crop the video to 1080 width/height

  


  


  ffmpeg -i ./files/video_small/$latestVideo -filter:v \"crop=1080:1080:420:0\" ./files/video_small/outcrop_$cod.mp4 2>&1");


  


  

  • first second should run normally

  


  


  ffmpeg.exe -t 1 -i ./files/video_small/outcrop_$cod.mp4 ./files/video_small/out1_$cod.mp4 2>&1");


  


  

  • the next two seconds will run at slow motion with a 2x factor

  


  


  ffmpeg.exe -ss 00:00:01 -t 2 -i ./files/video_small/outcrop_$cod.mp4 -filter_complex \"[0:v]setpts=2*PTS[v]\" -map \"[v]\" ./files/video_small/out2_$cod.mp4 2>&1");


  


  

  • the next second will speed up at 4x factor

  


  


  ffmpeg.exe -ss 00:00:03 -t 1 -i ./files/video_small/outcrop_$cod.mp4 -filter_complex \"[0:v]setpts=0.25*PTS[v]\" -map \"[v]\" ./files/video_small/out3_$cod.mp4 2>&1");


  


  

  • the next 2 seconds again slow motion

  


  


  ffmpeg.exe -ss 00:00:04 -t 2 -i ./files/video_small/outcrop_$cod.mp4 -filter_complex \"[0:v]setpts=2*PTS[v]\" -map \"[v]\" ./files/video_small/out4_$cod.mp4 2>&1");


  


  

  • final second again normal speed

  


  


  ffmpeg.exe -ss 00:00:06 -i ./files/video_small/outcrop_$cod.mp4 ./files/video_small/out5_$cod.mp4 2>&1");


  


  

  • concatenate the above parts to achieve the modified clip

  


  


  ffmpeg.exe -f concat -i ./files/video_small/files_$cod.txt -c copy  ./files/video_small/output1_$cod.mp4 2>&1");


  


  

  • then append the resulting clip in reverse

  


  


  ffmpeg -i ./files/video_small/output1_$cod.mp4 -filter_complex \"[0:v]reverse,fifo[r];[0:v][r] concat=n=2:v=1 [v]\" -map \"[v]\" ./files/video_small/output2_$cod.mp4 2>&1");


  


  

  • add watermark

  


  


  ffmpeg -i ./files/video_small/output2_$cod.mp4 -i ./files/watermark-video1080.png -filter_complex \"[0:v][1:v]overlay=(W-w)/2:10[outv]\" -map [outv] -c:v libx264 -crf 22 -preset veryfast ./files/video_small/output3_$cod.mp4 2>&1");


  


  

  • add audio (we can discard the original audio in any of the above steps)

  


  


  ffmpeg -i ./files/video_small/output3_$cod.mp4 -i ./files/video_small/sound-hip-hop.mp3 -map 0 -map 1:a -c:v copy -shortest ./files/video_small/output_final_$latestVideo 2>&1");


  


  Right now it runs ok, but I have a problem with performance, the whole process lasts about 50 seconds on my 8th gen i7.

  


  I am very new to the capabilities of ffmpeg and I was wondering if any of the below commands can be optimized or if any of the steps can be merged into one, as I can see the syntax is quite powerful.

  


  Thanks !

  


  I was expecting this to run a little bit faster, ideally half the time it takes right now.
As far as I have observed, the longest part is appending the resulting clip in reverse, perhaps I am adding something too heavy and unnecessary in the reverse filter.