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Sur d’autres sites (6463)

  • 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&#39;:
    getDuration.c:(.text+0x10): undefined reference to `av_register_all&#39;
    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 +_+

  • Live Photos on android implementation ?

    18 novembre 2016, par mohit gupta

    I have come up with a project which implements LIVE Photos capturing on android and I will hopefully make it open sourced,Spoiler : it takes a 1.5 second shot before and after you click the pic and combines them and make the video , While i tried it I was unable to do it with MediaRecorder in android , I even experimented with FFMPEG it just does not works . Anyone has any idea or a little light so i can follow and implement this.My min Api support is 16

  • ffmpeg Bmp to yuv : Crash at sws_scale

    28 décembre 2015, par the-owner

    The context :
    I have a succession of continuous bitmap and I want to encode them into a light video format.
    I use ffmpeg version 2.8.3 (the build here), under qt5, qt IDE, and msvc2013 for win32.

    The problem :
    My code crash at sws_scale () (and sometimes at avcodec_encode_video2()). When I explore the stack, the crash event occurs at sws_getCachedContext (). (I can only see the stack with these ffmpeg builds).
    I only use these ffmpeg libraries (from the Qt .pro file) :

    LIBS += -lavcodec -lavformat -lswscale -lavutil

    It’s swscale which bug. And this is the code :

    void newVideo ()
    {
       ULONG_PTR gdiplusToken;
       GdiplusStartupInput gdiplusStartupInput;
       GdiplusStartup(&amp;gdiplusToken, &amp;gdiplusStartupInput, NULL);

       initBitmap (); //init bmp
       int screenWidth =  bmp.bmiHeader.biWidth;
       int screenHeight = bmp.bmiHeader.biHeight;

       AVCodec * codec;
       AVCodecContext * c = NULL;
       uint8_t * outbuf;
       int i, out_size, outbuf_size;


       avcodec_register_all();

       qDebug () &lt;&lt; "Video encoding\n";

       // Find the mpeg1 video encoder
       codec = avcodec_find_encoder(AV_CODEC_ID_H264);
       if (!codec)
       {
           qDebug () &lt;&lt; "Codec not found\n";
           avcodec_close(c);
           av_free(c);
           return;
       }
       else
           qDebug () &lt;&lt; "H264 codec found\n";

       c = avcodec_alloc_context3(codec);

       c->bit_rate = 1000000;
       c->width = 800; // resolution must be a multiple of two (1280x720),(1900x1080),(720x480)
       c->height = 600;
       c->time_base.num = 1; // framerate numerator
       c->time_base.den = 25; // framerate denominator
       c->gop_size = 30; // emit one intra frame every ten frames
       c->max_b_frames = 1; // maximum number of b-frames between non b-frames
       c->pix_fmt = AV_PIX_FMT_YUV420P; //Converstion RGB to YUV ?
       c->codec_id = AV_CODEC_ID_H264;

       struct SwsContext* fooContext = sws_getContext(screenWidth, screenHeight,
                                                      AV_PIX_FMT_RGB32,
                                                      c->width, c->height,
                                                      AV_PIX_FMT_YUV420P,
                                                      SWS_FAST_BILINEAR,
                                                      NULL, NULL, NULL);

       // Open the encoder
       if (avcodec_open2(c, codec, NULL) &lt; 0)
       {
           qDebug () &lt;&lt; "Could not open codec\n";
           avcodec_close(c);
           av_free(c);
           return;
       }
       else qDebug () &lt;&lt; "H264 codec opened\n";

       outbuf_size = 100000 + c->width*c->height*(32>>3);//*(32>>3); // alloc image and output buffer
       outbuf = static_cast(malloc(outbuf_size));
       qDebug() &lt;&lt; "Setting buffer size to: " &lt;&lt; outbuf_size &lt;&lt; "\n";

       FILE* f = fopen("TEST.mpg","wb");
       if(!f) qDebug() &lt;&lt; "x - Cannot open video file for writing\n";
       else qDebug() &lt;&lt; "Opened video file for writing\n";

       // encode 5 seconds of video
       for (i = 0; i &lt; STREAM_FRAME_RATE*STREAM_DURATION; i++) //the stop condition i &lt; 5.0*5
       {
           qDebug () &lt;&lt; "i = " &lt;&lt; i;
           fflush(stdout);

           HBITMAP hBmp;
           if (GetScreen(hBmp) == -1) return;
           BYTE * pPixels;// = new BYTE [bmp.bmiHeader.biSizeImage];
           pPixels = getPixels (hBmp);
           DeleteObject (hBmp);

           int nbytes = avpicture_get_size(AV_PIX_FMT_YUV420P, c->width, c->height);
           uint8_t* outbuffer = (uint8_t*)av_malloc(nbytes*sizeof(uint8_t));
           if(!outbuffer) // check if(outbuf) instead
           {
               qDebug () &lt;&lt; "Bytes cannot be allocated";
               return;
           }

           AVFrame* inpic = avcodec_alloc_frame(); //av_frame_alloc () ?
           AVFrame* outpic = avcodec_alloc_frame();

           outpic->pts = (int64_t)((float)i * (1000.0/((float)(c->time_base.den))) * 90);
           if (avpicture_fill((AVPicture*) inpic, (uint8_t*) pPixels, AV_PIX_FMT_RGB32,
                          screenWidth, screenHeight) &lt; 0)
               qDebug () &lt;&lt;  "avpicture_fill Fill picture with image failed"; //Fill picture with image

           if(avpicture_fill((AVPicture*) outpic, outbuffer, AV_PIX_FMT_YUV420P,
                          c->width, c->height) &lt; 0)
               qDebug () &lt;&lt;  "avpicture_fill failed";

           if (av_image_alloc(outpic->data, outpic->linesize, c->width, c->height,
                          c->pix_fmt, 1) &lt; 0)
               qDebug () &lt;&lt;  "av_image_alloc failed";

           inpic->data[0] += inpic->linesize[0]*(screenHeight - 1); // Flipping frame
           inpic->linesize[0] = -inpic->linesize[0]; // Flipping frame

    ////////////////////////////HERE THE BUG////////////////////////////////
           sws_scale(fooContext,
                     inpic->data, inpic->linesize,
                     0, c->height,
                     outpic->data, outpic->linesize); //HERE THE BUG

           av_free_packet((AVPacket *)outbuf);
           // encode the image
           out_size = avcodec_encode_video2 (c, (AVPacket *) outbuf,
                                             (AVFrame *) outbuf_size, (int *) outpic);
    ///////////////////////THE CODE DONT GO BEYOND/////////////////////////////////

           qDebug () &lt;&lt; "Encoding frame" &lt;&lt; i &lt;&lt;" (size=" &lt;&lt; out_size &lt;&lt;"\n";
           fwrite(outbuf, 1, out_size, f);
           delete [] pPixels;
           av_free(outbuffer);
           av_free(inpic);
           av_freep(outpic);
       }

       // get the delayed frames
       for(; out_size; i++)
       {
           fflush(stdout);
           out_size = avcodec_encode_video2 (c, (AVPacket *) outbuf,
                                             (AVFrame *) outbuf_size, NULL);
           qDebug () &lt;&lt; "Writing frame" &lt;&lt; i &lt;&lt;" (size=" &lt;&lt; out_size &lt;&lt;"\n";
           fwrite(outbuf, 1, out_size, f);
       }

       // add sequence end code to have a real mpeg file
       outbuf[0] = 0x00;
       outbuf[1] = 0x00;
       outbuf[2] = 0x01;
       outbuf[3] = 0xb7;
       fwrite(outbuf, 1, 4, f);
       fclose(f);

       avcodec_close(c);
       free(outbuf);
       av_free(c);
       qDebug () &lt;&lt; "Closed codec and Freed\n";
    }

    And the output :

    Video encoding

    H264 codec found

    H264 codec opened

    Setting buffer size to:  2020000

    Opened video file for writing

    i =  0
    **CRASH**

    I have thougth that my bitmap wasn’t good so I have crafted a bitmap just for testing, the code was :

       uint8_t* pPixels = new uint8_t[Width * 3 * Height];
       int x = 50;
       for(unsigned int i = 0; i &lt; Width * 3 * Height; i = i + 3) // loop for generating color changing images
       {
           pPixels [i] = x % 255; //R
           pPixels [i + 1] = (x) % 255; //G
           pPixels [i + 2] = (255 - x) % 255; //B
       }

    However the crash continue. Perhaps, it might prove that it’s not the bitmap (pPixels) which has a problem.

    If anyone know, why I get this bug : Maybe don’t I set one parameter well ? Or one ffmpeg deprecated function ? etc.


    EDIT 1 27/12/15

    Thanks to Ronald S. Bultje The function sws_scale () does not crash with this code, however I get an error from it bad dst image pointers. My code :

    //DESTINATION FRAME            
    if (avpicture_alloc ((AVPicture*) dst_frame, AV_PIX_FMT_YUV420P, c->width, c->height) &lt; 0)
               {
                   qDebug () &lt;&lt;  "# avpicture_alloc failed";
                   return;
               }
               if(avpicture_fill((AVPicture*) dst_frame, NULL, AV_PIX_FMT_YUV420P,
                              c->width, c->height) &lt; 0)
                   qDebug () &lt;&lt;  "avpicture_fill failed";
               avcodec_align_dimensions2 (c, &amp;c->width, &amp;c->height, dst_frame->linesize);

    //SOURCE FRAME
               if (avpicture_fill((AVPicture*) src_frame, (uint8_t *) pPixels, AV_PIX_FMT_RGB32,
                                  tmp_screenWidth, tmp_screenHeight) &lt; 0)
                   qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image
               avcodec_align_dimensions2 (c, &amp;tmp_screenWidth, &amp;tmp_screenHeight, src_frame->linesize);

               struct SwsContext* conversionContext = sws_getContext(tmp_screenWidth,tmp_screenHeight,AV_PIX_FMT_RGB32,c->width, c->height, AV_PIX_FMT_YUV420P,SWS_FAST_BILINEAR, NULL, NULL, NULL);

               int output_Height = sws_scale(conversionContext,
                                             src_frame->data, src_frame->linesize,
                                             0, tmp_screenHeight,
                                             dst_frame->data, dst_frame->linesize); //return 0 -> bad dst image pointers error

    EDIT 2 28/12/15

    I have tried to follow the Ronald S. Bultje’s suggestion and now I get a bad src image pointers error, I have investigated and worked many hours but I do not find a solution. Here, there is the new snippet :

    AVFrame* src_frame = av_frame_alloc ();
    AVFrame* dst_frame = av_frame_alloc ();
    AVFrame* tmp_src_frame = av_frame_alloc ();

    /*........I do not use them until this snippet..........*/
    //DESTINATION
    //avpicture_free ((AVPicture*)dst_frame);
    avcodec_align_dimensions2 (c, &amp;c->width, &amp;c->height, dst_frame->linesize);
    if (avpicture_alloc ((AVPicture*) dst_frame, AV_PIX_FMT_YUV420P, c->width, c->height) &lt; 0)
    {
       qDebug () &lt;&lt;  "# avpicture_alloc failed";
       return;
    }

    //SOURCE
    //stride = src_frame->linesize [0] = ((((screenWidth * bitPerPixel) + 31) &amp; ~31) >> 3); do I need to do that ?
    //== stride - I have gotten this formula from : https://msdn.microsoft.com/en-us/library/windows/desktop/dd318229(v=vs.85).aspx
    if (avpicture_fill((AVPicture*) src_frame, (uint8_t *) pPixels, AV_PIX_FMT_RGB32,
                      screenWidth, screenHeight) &lt; 0)
       qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image
    //linesize [0] == 21760 like commented stride

    //Source TO TMP Source
    avcodec_align_dimensions2 (c, &amp;tmp_screenWidth, &amp;tmp_screenHeight, tmp_src_frame->linesize);
    if (avpicture_fill((AVPicture*) tmp_src_frame, NULL, AV_PIX_FMT_RGB32,
                      tmp_screenWidth, tmp_screenHeight) &lt; 0)
       qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image

    av_picture_copy ((AVPicture*) tmp_src_frame, (const AVPicture*) src_frame, AV_PIX_FMT_RGB32,
                    screenWidth, screenHeight);

    struct SwsContext* conversionContext = sws_getContext(tmp_screenWidth, tmp_screenHeight,
                                                         AV_PIX_FMT_RGB32,
                                                         c->width, c->height,
                                                         AV_PIX_FMT_YUV420P,
                                                         SWS_FAST_BILINEAR,
                                                         NULL, NULL, NULL);

    int output_Height = sws_scale(conversionContext,
                                 tmp_src_frame->data, tmp_src_frame->linesize,
                                 0, tmp_screenHeight,
                                 dst_frame->data, dst_frame->linesize);
    //ffmpeg error = bad src image pointers
    // output_Height == 0

    EDIT 3

    For temp Picture I have done an avcode_align_dimension2() then a avpicture_alloc() for allocating memory and avpicture_fill() in order to fill the picture pointer. Below the updated code :

    //DESTINATION
    //avpicture_free ((AVPicture*)dst_frame);
    avcodec_align_dimensions2 (c, &amp;c->width, &amp;c->height, dst_frame->linesize);
    if (avpicture_alloc ((AVPicture*) dst_frame, AV_PIX_FMT_YUV420P, c->width, c->height) &lt; 0)
    {
       qDebug () &lt;&lt;  "# avpicture_alloc failed";
       return;
    }

    //SOURCE
    //src_frame->linesize [0] = ((((screenWidth * bpp) + 31) &amp; ~31) >> 3);
    //src_frame->linesize [0] = stride;
    if (avpicture_fill((AVPicture*) src_frame, (uint8_t *) pPixels, AV_PIX_FMT_RGB32,
                      screenWidth, screenHeight) &lt; 0)
       qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image

    //Source TO TMP Source
    avcodec_align_dimensions2 (c, &amp;tmp_screenWidth, &amp;tmp_screenHeight, tmp_src_frame->linesize);
    if (avpicture_alloc ((AVPicture*) tmp_src_frame, AV_PIX_FMT_RGB32, tmp_screenWidth, tmp_screenHeight) &lt; 0)
    {
       qDebug () &lt;&lt;  "# avpicture_alloc failed";
       return;
    }
    int outbuf_size = tmp_screenWidth*tmp_screenHeight*4;// alloc image and output buffer
    outbuf = static_cast(malloc(outbuf_size));
    if (avpicture_fill((AVPicture*) tmp_src_frame, outbuf, AV_PIX_FMT_RGB32,
                      tmp_screenWidth, tmp_screenHeight) &lt; 0)
       qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image
    av_picture_copy ((AVPicture*) tmp_src_frame, (const AVPicture*) src_frame, AV_PIX_FMT_RGB32,
                    tmp_screenWidth, tmp_screenHeight);

    struct SwsContext* conversionContext = sws_getContext(tmp_screenWidth, tmp_screenHeight,
                                                         AV_PIX_FMT_RGB32,
                                                         c->width, c->height,
                                                         AV_PIX_FMT_YUV420P,
                                                         SWS_FAST_BILINEAR,
                                                         NULL, NULL, NULL);

    int output_Height = sws_scale(conversionContext,
                                 tmp_src_frame->data, tmp_src_frame->linesize,
                                 0, tmp_screenHeight,
                                 dst_frame->data, dst_frame->linesize);

    The call stack is as follow : av_picture_copy() is called then av_image_copy() then _VEC_memcpy() then fastcopy_I() and crash ... The problem is not the dimensions (tmp_screenWidth/Height) ? (With av_picture_copy () could we copy a picture P1 with dim W1xH1 to a picture P2 with dimension W2xH2 ?)

    EDIT 4

    Crash at av_picture_copy() which call _aligned_malloc() then av_image_copy _VEC_memcpy() and fastcopy_I()

    //SOURCE
    if (avpicture_fill((AVPicture*) src_frame, (uint8_t *) pPixels, AV_PIX_FMT_RGB32,
                      screenWidth, screenHeight) &lt; 0)
       qDebug () &lt;&lt;  "# avpicture_fill Fill picture with image failed"; //Fill picture with image

    //Source TO TMP Source
    avcodec_align_dimensions2 (c, &amp;tmp_screenWidth, &amp;tmp_screenHeight, tmp_src_frame->linesize);
    if (avpicture_alloc ((AVPicture*) tmp_src_frame, AV_PIX_FMT_RGB32, tmp_screenWidth, tmp_screenHeight) &lt; 0)
    {
       qDebug () &lt;&lt;  "# avpicture_alloc failed";
       return;
    }
    av_picture_copy ((AVPicture*) tmp_src_frame, (const AVPicture*) src_frame, AV_PIX_FMT_RGB32,
                    tmp_screenWidth, tmp_screenHeight);