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  • Converted mp4 not displaying image which was added with FFMPEG [duplicate]

    3 décembre 2015, par Avi

    This question already has an answer here:

    I am converting a mp3 to a mp4 and simultaneously adding an image to it using FFMPEG.

    Here is the command I am using.

    ffmpeg -loop 1 -i ../image.jpg -i "track 1.mp3" -c:v libx264 -c:a aac -strict experimental -b:a 192k -shortest -vf scale=800:400 "track 1".mp4

    The image appears when the video is played in a web browser. However, it doesn't appear when the video is played on Windows Media Player or on QuickTime.

    Any ideas why?

  • creation of video file with alpha channel/transparency

    3 décembre 2015, par boerfi

    I'm experimenting with a video file with alpha channel. Later on the file should be an overlay for another video. It will be merged with another file in real time and saved to another file. But that is not the important point. The problem starts earlier because I can't even play it.

    The video is a png-encoded Quicktime-file which I cannot play with any video player. WMP, VLC, MPC and ffplay all show various problems which all lead to the problem that the images seem to get decoded too slowly. The strange thing is that neither cpu (i7) nor my ssd are on limit but the file isn't played correctly.

    Since the problem appears with all players I think it's based on using png in video. I googled but didn't find a proper way to create a partly transparent video file. I tried various methods of exporting (with adobe media encoder) with no result: the file lost its transparency or is running too slow.

    The resulting file which I create with my SDK is correct (video and audio are synchronous and fluid) but it takes 1 minute to render a video of 40 seconds although it works in real time with files without transparency.

    Does anyone know what kind of file I should export that has a minimum resolution of 720p, that is partly transparent and that can be played with ffplay in real time? I would also appreciate any experiences with partly transparent videos which could help me because I couldn't find any helpful links?

    Thanks, Marius

  • Unresolved external symbol when linking ffmpeg/avcodec with Visual Studio 2015 ?

    2 décembre 2015, par Ragnar

    I'm trying to build ffmpeg/avcodec library with Visual Studio 2015 and it gives me following linking error:

    allcodecs.obj : error LNK2001: unresolved external symbol ff_h263_vaapi_hwaccel 
allcodecs.obj : error LNK2001: unresolved external symbol ff_h263_vdpau_hwaccel
allcodecs.obj : error LNK2001: unresolved external symbol ff_h263_videotoolbox_hwaccel
...

    The problem comes from this macro https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/allcodecs.c#L34

    #include "config.h"
#include "avcodec.h"
#include "version.h"

...

#define REGISTER_HWACCEL(X, x)                                      \
    {                                                               \
        extern AVHWAccel ff_##x##_hwaccel;                          \
        if (CONFIG_##X##_HWACCEL)                                   \
            av_register_hwaccel(&ff_##x##_hwaccel);                 \
    }

...

void avcodec_register_all(void)
{
    static int initialized;

    if (initialized)
        return;
    initialized = 1;

    /* hardware accelerators */
    REGISTER_HWACCEL(H263_VAAPI,        h263_vaapi);
    REGISTER_HWACCEL(H263_VIDEOTOOLBOX, h263_videotoolbox);
    ...

    I don't understand why do these methods even get declared when my config has them set to 0

    #define CONFIG_H263_VAAPI_HWACCEL 0
#define CONFIG_H263_VDPAU_HWACCEL 0
#define CONFIG_H263_VIDEOTOOLBOX_HWACCEL 0
...

    Btw it builds OK when I use msys/make tooling.

  • ffmpeg streaming from camera

    2 décembre 2015, par Nycholas

    I'm with a code to make a stream of the camera to an address, however, is not working properly, because nothing comes in VLC. Apparently, the problem is that I can not post the video of the webcam by the network, but I can usually save a file. I think it's a mistake in relation to PTS, however, do not know much what to do. Could help me with the code?Here is the code

  • Ffmpeg, extract video from live stream, merge with other audio source and streaming output in rmtp

    2 décembre 2015, par Vinzit

    I'm tryng with this 

    ffmpeg -f mpegts -i "udp://x.x.x.x:8554??fifo_size=100&overrun_nonfatal=1":audio="audio_device" -map 0:v:0 -map 1:a:0 -f flv "rtmp://x.x.x.x:1935/live/app/gopro"

    this is the message:

    [mpegts @ 00000000004437a0] Could not find codec parameters for stream 2 (Unknown: none ([128][0][0][0] / 0x0080)): unknown codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, mpegts, from 'udp://x.x.x.x:8554??fifo_size=100&overrun_nonfatal=1:audio=audio_device:
  Duration: N/A, start: 9.685333, bitrate: N/A
  Program 1
    Stream #0:0[0x1011]: Video: h264 (Main) ([27][0][0][0] / 0x001B), yuvj420p(pc, bt709), 432x240 [SAR 1:1 DAR 9:5], 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:1[0x1100]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 130 kb/s
    Stream #0:2[0x200]: Unknown: none ([128][0][0][0] / 0x0080)
Invalid input file index: 1.

    I'm newbie in ffmpeg, can anyone help me?

    Thanks in advance,

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