Recherche avancée

Sur d’autres sites (6430)

• Deploy application with accord.video.ffmpeg c#

  14 avril 2017, par Alex Gimondi

  I’m using accord.video.ffmpeg 3.4.0, downloaded via nuget, to save a video with videorecorder class. If I compile (x86) my solution the application is running smoothly in visual studio, instead if I publish the app (same architecture ) when I try to run the setup.exe it installs the program but suddenly crashes. The problem is in the constructor of a class when I do new videorecorder(). It is like If during the deployment process not all the libraries needed are included.
  Anyonw knows which libraries are missing ?
  Thank,
  Alex

• Building FFMPEG library for iOS6.0 ARMv7 Processor

  15 août 2013, par Jimmy

  WARNING :

  I was just informed by another user that there are some legal issues revolving around using FFMPEG for iOS, leaving the link here http://multinc.com/2009/08/24/compatibility-between-the-iphone-app-store-and-the-lgpl/

  I cleaned up my question a little bit, when I wrote it the first time I was flustered. Now I can be more clear after taking a small break.

  Edit : learned that you have to build for ARMv7, ARMv7s and iOS6.0

  I'm trying to use the FFMPEG library in an XCode 4.5.1 project. And I'm trying to build it for ARMv7. What I'm looking for is the exact process, and some explanation. I understand that this is not a well documented problem. But I know that other pople have had the same problem as me.

  What I have been able to do.

  I have been able to build the library for testing.

  1) I have been able to clone ffmpeg. For beginners this will get you started by creating a directory with the ffmpeg source. (Kudos to the guys who wrote it)

  git clone git ://source.ffmpeg.org/ffmpeg.git ffmpeg

  2) I have been able to write a config file that doesn't have any errors. We will go back to this part later. This is the command I attach to ./configure

  ./configure
  —disable-doc
  —disable-ffmpeg
  —disable-ffplay
  —disable-ffserver
  —enable-cross-compile
  —arch=arm
  —target-os=darwin
  —cc=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/llvm-gcc-4.2/bin/arm-apple-darwin10-llvm-gcc-4.2

  —as='gas-preprocessor/gas-preprocessor.pl /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/llvm-gcc-4.2/bin/arm-apple-darwin10-llvm-gcc-4.2'

  —sysroot=/applications/xcode.app/contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk

  —cpu=cortex-a8
  —extra-ldflags='-arch=armv7 -isysroot /applications/xcode.app/contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk'
  —enable-pic —disable-bzlib —disable-gpl —disable-shared —enable-static —disable-mmx —disable-debug —disable-neon —extra-cflags='-pipe -Os -gdwarf-2 -isysroot /applications/xcode.app/contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk
  -m$thumb_opt :-no-thumb -mthumb-interwork'

  These are some things to note.

  • I had to download ( https://github.com/yuvi/gas-preprocessor ) copy the file gas-preprocessor.pl at /usr/local/bin. Set permissions to read write (777)
  • Make sure I'm using the right GCC compiler : /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/llvm-gcc-4.2/bin/arm-apple-darwin10-llvm-gcc-4.2
  • Make sure I'm using the right SDK : /applications/xcode.app/contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk
  • —extra-cflags="-arch armv7" causes : error : unrecognized command line option “-arch”

  Here in lies the problem.

  I can include the library like so

  libavcodec/avcodec.h

  But when I started to write the encoder. I received this warning, and countless errors.

  ignoring file /Users/Jimmy/Development/source.ffmpeg/Library/libavutil.a, file was built for archive which is not the architecture being linked (armv7s) : /Users/Jimmy/Development/source.ffmpeg/Library/libavutil.a

  That means that I didn't build the right binary.

  What I'm looking for is someone whose done it before, to walk all of us through the process of building FFMPEG for iOS6.0 and ARMv7 and the majority of things to look out for. Thanks a ton.

• X264 & ARM encoding on Android

  20 janvier 2013, par Tishu

  I recently built a Video encoding class that runs on Android using ffmpeg and native code. I am surprised by the time it takes to encode a video, about 1 frame / second at best. I have tried with x264 and settings optimised for speed and with mpeg as well - no real difference.

  The x264 library now has support for ARM architecture and is meant to be quite efficient on these boasting over 20fps encoding speed. I am not sure I am using it correctly. Here the script I use for compiling :

  ./configure --prefix=$PREFIX \
  
  --enable-shared \
  
  --enable-static \
  
  --disable-gpac \
  
  --enable-debug \
  
  --extra-cflags=" -I$ARM_INC -fPIC -DANDROID -fpic -mthumb-interwork -ffunction-sections -funwind-tables -fno-short-enums -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -Wno-psabi -march=armv5te -msoft-float -mthumb -O3 -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 -DANDROID -Wa,--noexecstack -MMD -MP " \
  
  --extra-ldflags=" -nostdlib -Bdynamic -Wl,--no-undefined -Wl,-z,noexecstack -Wl,-z,nocopyreloc -Wl,-soname,/usr/lib/libz.so -Wl,-rpath-link=$ARM_LIB,-dynamic-linker=/system/bin/linker -L$ARM_LIB -lc -lm -ldl -lgcc" \
  
  --cross-prefix=${ARM_PRE}- \
  
  --disable-asm \
  
  --host=arm-linux \

  I believe the last line should so what I am after ie enable ARM optimisations. Maybe I am missing something.

  For info I am encoding a 640x480 video on a Nexus 7 tablet. Here are my encoder settings (x264)

  c->gop_size       = 12;
  
  c->pix_fmt        = PIX_FMT_YUV420P;
  
  c->max_b_frames   = 0;
  
  c->scenechange_threshold = 0;
  
  c->rc_buffer_size = 0;

  Thanks