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• Adding a image resource over video file from sd card using ffmpeg or MediaMuxer for android

  18 septembre 2014, par Alin

  I am stuck in this area which I am not comfortable at all to work in.

  Here is what I did so far :

  • Made an Ubuntu VirtualBox machine
  • Downloaded latest ffmpeg version which is 2.3.3
  • Compiled ffmpeg to be compatible with armv7-a so in the end I get two folders : include and lib. In include I have the headers and in libs the *.so files (just as in http://www.roman10.net/how-to-build-ffmpeg-with-ndk-r9/)

  

  I have created a new android project and made a jni folder and this is how far I went... Even this, with all the struggle being new to linux and compiling took me almost a week to reach.

  Adding a watermark in ffmpeg I believe it is done on libavfilter ? I have to dig on this matter, however the original ffmpeg I need to translate into my project is :

  ffmpeg -i input.avi -i logo.png -filter_complex 'overlay=10:main_h-overlay_h-10' output.avi

  As far as I am studying now I need to do inside jni :

  • create a add_watermark.c file in which I need to somehow call the function that does the filter overlay call

  • create Android.mk to load this and the ffmpeg needed libraries

    LOCAL_PATH := $(call my-dir)

    include $(CLEAR_VARS)

    LOCAL_MODULE := add-watermark

    LOCAL_SRC_FILES := add-watermark.c

    LOCAL_LDLIBS := -llog -ljnigraphics -lz

    LOCAL_SHARED_LIBRARIES := libavformat libavcodec libswscale libavutil

    include $(BUILD_SHARED_LIBRARY)

    $(call import-module,ffmpeg-2.3.3/android/armv7-a)

  • create Application.mk

    APP_ABI := armeabi-v7a

    APP_PLATFORM := android-8

  • run ndk-build and use the generated libraries in my android project.

  I really need help on continuing, so every answer is received with great attention and pleasure.

  Later Edit :
  Would it be possible to somehow build ffmpeg.exe as a library and call its main with the exact same parameters as the original exe ? I do not want to run ffmpeg as a standalone executable, but have it integrated within the project. Something like http://www.roman10.net/how-to-port-ffmpeg-the-program-to-androidideas-and-thoughts/ What downsides would this approach have ?

  Later edit 2 : if this is possible by using MediaMuxer or other APIs added in android 4.3 I am open to it you sample codes are provided. I did look over the MediaCodec and MediaMuxer samples also Grafik and haven’t found a proper way to do what I wanted. I prefer ffmpeg approach better if it works

• extracting header information of video file

  1er juin 2021, par david

  I have some video files that encode them using FFmpeg and produce mp4 files. now I need to extract header information of video files and dump this information (like the size of macroblock, motion vector,...) into a file and use this information for feature extraction. but I do not know how can I extract header information. do you know any software or sth like this for extracting header information. I used JM software and xmltracefile, but it doesn't work and produce lots of errors. if you have any suggestions or tutorials for this issue please let me know. Thank you.

  


• Revision cdc954fdc8 : skip the un-necessary motion search in the first pass This patch allows the VP9

  16 juin 2014, par Pengchong Jin

  Changed Paths :
   Modify /vp9/encoder/vp9_firstpass.c

  
  
  skip the un-necessary motion search in the first pass

  This patch allows the VP9 encoder to skip the un-necessary
  motion search in the first pass. It computes the motion error
  of 0,0 motion using the last source frame as the reference,
  and skips the further motion search if this error is small.

  Borg test shows overall the patch gives PSNR gain (derf -0.001%,
  yt 0.341%, hd 0.282%). Individual clips may have PSNR gain or
  loss. The best PSNR performance is 7.347% and the worst is -0.662%.
  The first pass encoding speedup for slideshow clips is over 30%.

  Change-Id : I4cac4dbd911f277ee858e161f3ca652c771344fe