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• calling ffmpeg from java on android [closed]

  8 mai 2012, par Lior

  Possible Duplicate :
  FFMPEG on Android

  Currently I have a java application that calls ffmpeg process with parameters.
  This works fine under Windows because I just run another process.
  I want to call the same method in ffmpeg api under android os.

  What should I do in order to have minimal change in code and transform the same thing to android ?

  How can I call, using java, a specific method in ffmpeg api under the android os.

  thank you !

• Merge commit ’f1ccd076801444ab7f524cb13e0886faaf10fd50’

  17 décembre 2015, par Hendrik Leppkes

  Merge commit ’f1ccd076801444ab7f524cb13e0886faaf10fd50’
  * commit ’f1ccd076801444ab7f524cb13e0886faaf10fd50’ :
  
    h264 : do not call frame_start() for missing frames
  Not merged, FFmpeg does a lot more in frame_start to setup missing frames
  
  as well (like coloring them), and the overhead of the other setup is
  
  minimal.
  Merged-by : Hendrik Leppkes <h.leppkes@gmail.com>
  

• Libav FFv1 read_quant_table decoding errors

  16 novembre 2023, par flansel

  I am having trouble encoding and decoding video using the 'ffv1' codec. Interestingly when the width and height are 640 or less, this works correctly, but with any "large" frame size such as 1280x720 I get the follow errors ...

  


  [ffv1 @ 0x5612f4ab2240] read_quant_table error
[ffv1 @ 0x5612f4ab2240] Cannot decode non-keyframe without valid keyframe


  


  Are there any options which need to be set, or am I doing something else incorrectly, I made the example very minimal, I am aware that I am not writing an image to the frame and simply allocating garbage in the buffers among other things.
Thanks in advance.

  


  // minimal example
// ...
#define FRAMES (500)

int main(int argc, char **argv)
{
    AVCodecContext *enc, *dec;
    AVFrame *frame = av_frame_alloc();
    AVFrame *decoded_frame = av_frame_alloc();
    AVPacket *packet = av_packet_alloc();
    AVPacket *padded_packet = av_packet_alloc();

    const AVCodec *enc_codec = avcodec_find_encoder_by_name("ffv1");
    const AVCodec *dec_codec = avcodec_find_decoder_by_name("ffv1");
    enc = avcodec_alloc_context3(enc_codec);
    dec = avcodec_alloc_context3(dec_codec);

    enc->width   = 1280;
    enc->height  = 720;
    enc->pix_fmt = AV_PIX_FMT_YUV420P;
    enc->time_base.num = 1001;
    enc->time_base.den = 60000;

    dec->width  = enc->width;
    dec->height = enc->height;

    avcodec_open2(enc, enc_codec, NULL);
    avcodec_open2(dec, dec_codec, NULL);

    frame->height = enc->height;
    frame->width  = enc->width;
    frame->format = enc->pix_fmt;
    av_frame_get_buffer(frame, 32);
    printf("frame linesz %i,%i,%i\n", frame->linesize[0], frame->linesize[1], frame->linesize[2]);

    for (int i = 0; i < FRAMES; ++i)
    {
        avcodec_send_frame(enc, frame);
        while (!avcodec_receive_packet(enc, packet))
        {
            av_new_packet(padded_packet, packet->size + AV_INPUT_BUFFER_PADDING_SIZE);
            padded_packet->size -= AV_INPUT_BUFFER_PADDING_SIZE;

            memset(padded_packet->data, 0, padded_packet->size);
            memcpy(padded_packet->data, packet->data, packet->size);
            printf("frame %i encoded %i bytes\n", i, padded_packet->size);
            if (!avcodec_send_packet(dec, padded_packet))
            {
                printf("sent bytes to decoder\n");
            }
        }

        while (!avcodec_receive_frame(dec, decoded_frame))
        {
            printf("decoded frame height %i, width %i\n", decoded_frame->height, decoded_frame->width);
        }
        usleep(16000);
    }
    return 0;
}