Sur d’autres sites (7242)

• While working with ffmpeg : Created function in C file and after compilation with NDK accessing from android activity, getting signal 11 error

  30 mai 2016, par Dayanand Lande

  After successfully fire command ndk-build I got .so file in my libs folder, then after some changes in gradle file I got native_libs.xml .idea/libraries folder.

  Now I am accessing c function from my java code/ android activity. I am getting signal 11 error

  My code is

  C file

  #include 
  
  #include <android></android>log.h>
  
  #include 
  
  
  
  #include "libavcodec/avcodec.h"
  
  #include "libavformat/avformat.h"
  
  
  
  #define LOG_TAG "mylib"
  
  #define LOGI(...)  __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
  
  #define LOGE(...)  __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
  
  
  
  
  
  //JNIEXPORT jint JNICALL Java_com_xxx_xxx_activities_SplashActivity_logFileInfo(JNIEnv * env, jobject this, jstring filename);
  
  
  
  jint Java_com_xxx_xxx_activities_TutorialsActivity_logFileInfo(JNIEnv * env, jobject this, jstring filename)
  
  {
  
      av_register_all();
  
  
  
      AVFormatContext *pFormatCtx;
  
      const jbyte *str;
  
      str = (*env)->GetStringUTFChars(env, filename, NULL);
  
  
  
      if(avformat_open_input(&amp;pFormatCtx, str, NULL, NULL)!=0)
  
      {
  
          LOGE("Can't open file '%s'\n", str);
  
          return 1;
  
      }
  
      else
  
      {
  
          LOGI("File was opened\n");
  
          LOGI("File '%s', Codec %s",
  
              pFormatCtx->filename,
  
              pFormatCtx->iformat->name
  
          );
  
      }
  
      return 0;
  
  }

  Loading and try to access method in java code is

  private static native int logFileInfo(String filename);
  
  
  
  
  
      static {
  
          System.loadLibrary("framegrabber");
  
      }

  In OnCreate of activity

  logFileInfo(file.getAbsolutePath());

  Finally error at point logFileInfo(file.getAbsolutePath()); is

  A/libc: Fatal signal 11 (SIGSEGV), code 1, fault addr 0x106e in tid 8905 (Thread-20972)

  Please replay if you have any solution, Thanking in advance.

• ffmpeg : Dynamically set output duration based on sliding text width

  18 janvier 2016, par John Whiteman

  I need to create a smooth ’news ticker’ on a low powered android device. Unfortunately this is impossible at runtime using HTML or native code as there is always some stutter or glitch.

  I’ve created a solution that gives me a smooth result by encoding an mp4 for each message and displaying one video after the other. This is the code I’m using :

  ffmpeg -f lavfi -i color=c=black:s=1280x100 -vf "drawtext=BebasNeue.otf:fontsize=60:fontcolor=white:y=h-line_h-30:x=-(4*n)+1280:text='Hello world'" -t 10 output.mp4

  Problem :
  I need to set the video’s duration dynamically so that the video stops when the text has completed it’s journey from right to left. The messages will be of varying lengths and I need each message to scroll at a constant speed (ie. an mp4 with a longer message would have a longer duration).

  Is this possible via an expression ? If not is there some clever way I can calculate this outside of ffmpeg and pass it to the ’-t’ (duration) parameter ?

  ** Edit **
  To calculate outside of ffmpeg I can do a calculation like video_width + text_width / video_fps (ie. 1280 + 262 / 25) to give me the duration. So now I’m just looking to see if this is possible within the ffmpeg command line itself. t

  Many thanks

• How can I download a video with url beginning with blob:https://…

  11 août 2017, par iMax

  I would like to know if it is possible to download a video from a URL beginning with blob :

  blob:https://www.xyz123…

  i would prefer a terminal solution (ffmpeg ?, youtube-dl ?). but i have not found anything on the world wide web.

  Again : I have the url of the video stream, which looks like the above. How can I download the complete video ?

  Update

  Ok. I now found a webpage which allowed me to download the video file I wanted :
  https://video-download.online/

  But I am still wondering if there is a Terminal solution for downloading video with blob-URL (like in arte mediathek [ example arte ] or in zdf mediathek [ example zdf ]).

  Does nobody know how to do it ?