Recherche avancée

Sur d’autres sites (8025)

• Ubuntu12.04 : libavformat header trouble when compiling C program

  30 mai 2013, par Juneyoung Oh

  My code is super simple, just include "avformat.h" and call "av_register_all".

  full code is below.

    1 #include 
  
    2 #include 
  
    3 #include 
  
    4 //#include <libavcodec></libavcodec>avcodec.h>
  
    5 #include <libavformat></libavformat>avformat.h>
  
    6 //#include "libavcodec/avcodec.h"
  
    7 //#include "libavformat/avformat.h"
  
    8 
  
    9 
  
   10 int main (int argc, char* argv[]){
  
   11         av_register_all();
  
   12 /*
  
   13         AVFormatContext* pFormatCtx;
  
   14         const char* filename = "/home/juneyoungoh/Videos/CON1234ID.ts";
  
   15 
  
   16         if(av_open_input_file(&amp;pFormatCtx, filename, NULL, 0, NULL) != 0)
  
   17         {
  
   18                 handle_error();
  
   19         }
  
   20 
  
   21         if(av_find_stream_info(pFormatCtx) &lt; 0)
  
   22         {
  
   23                 handle_error();
  
   24         }
  
   25 
  
   26         dump_format(pFormatCtx, 0, filename, 1);
  
   27 
  
   28         //av_get_audio_frame_duration();
  
   29 */
  
   30         return 0;
  
   31 }

  The problem is when I compile this in Terminal it show error.

  /tmp/ccvgpGjv.o: In function `main':
  
  getDuration.c:(.text+0x10): undefined reference to `av_register_all'
  
  collect2: ld returned 1 exit status

  my avformat.h file is in /usr/local/include/libavformat/avformat.h.

  Here is something I have already tried.

  1. gcc getDuration.c
  2. gcc -I/usr/local/include/ getDuration.c
  3. gcc -I/usr/local/include/libavformat/ getDuration.c
  4. gcc -L/usr/local/include/ getDuration.c
  5. gcc -L/usr/local/include/libavformat/ getDuration.c
  6. gcc getDuration.c -lavformat

  Give me the light of hope +_+

• geting no result from GetStringUTFChars JNI

  9 avril 2013, par talhamalik22

  android NDK for my android application. i am stuck on the starting lines and it is not compiling further. Following is my code. It doest not compile after "str = (*env)->GetStringUTFChars(env, filename, NULL) ;". Please check my java and c code

  The java code :

  public class MyffmpegActivity extends Activity {
  
  
  
  private static native int logFileInfo(String filename);
  
  
  
  static
  
  {
  
      Log.i("HEHA", "HOHA");
  
      System.loadLibrary("mylib");
  
  }
  
  
  
  @Override
  
  protected void onCreate(Bundle savedInstanceState) {
  
      super.onCreate(savedInstanceState);
  
      setContentView(R.layout.activity_myffmpeg);
  
      String path=Environment.getExternalStorageDirectory().getPath();
  
      path=path+"/test.mp4";
  
      Log.i("Name Returned is ", ":"+path);
  
  int x=logFileInfo(path);
  
  
  
  
  
  }

  The C code

  jint Java_com_example_myffmpegtest_MyffmpegActivity_logFileInfo(JNIEnv * env, jobject  this, jstring filename)
  
  {
  
  
  
  av_register_all();
  
     AVFormatContext *pFormatCtx;
  
     const jbyte *str;
  
  
  
    str = (*env)->GetStringUTFChars(env, filename, NULL);
  
   if(av_open_input_file(&pFormatCtx, str, NULL, 0, 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;}

• How to make a videoplayer using FFmpeg on android ndk

  24 juillet 2012, par LMDS

  I'm trying to make a Video Player using ffmpeg and I use this tutorial http://dranger.com/ffmpeg/tutorial08.html, what I understand this tutorial convert a video to a video Image YUV, I'm trying to make the file that interact from .c to .java, I have this

  code c from the tutorial08(http://dranger.com/ffmpeg/tutorial08.c), then I made

  public class RtspReceiver extends Activity

  public SurfaceView sfv;
  
  @Override
  
  public void onCreate(Bundle savedInstanceState) {
  
      super.onCreate(savedInstanceState);
  
      setContentView(R.layout.principal);
  
      sfv=(SurfaceView) findViewById(R.id.im);
  
  }
  
  
  
  /* load our native library */
  
  static {
  
      System.loadLibrary("Interface");
  
  }
  
  
  
  private static native void Receive(SurfaceView  sf);

  In the c I'm trying to understand how I can use this

  JNIEXPORT void JNICALL isec_projecto_rtspreceiver_RtspReceiver_Receive(JNIEnv * env, jobject  obj, jobject Surface)
  
  {
  
  //what I have to put in here?
  
  }

  How can I put the SurfaceView that I have in the java, in the c ???
  and other thing, in the tutorial08.c how can I extract the video and put them in the java ? am I thinking correctly ?