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Posted: **11 Dec 2011 21:38**

Hi im using libvlc_video_get_aspect_ratio to determine if user has selected a special aspect ratio on current video.

These function returns a pointer to a char, and on documentation ive readed that pointer needs to be released using free() or libvlc_free(). But when i try to release these pointer with free() function i get an assertion on the next line of visual studio crt (NOTE i only try to release these pointer when it not returns NULL, for example returns "16:9"):

Code: Select all

/*
         * If this ASSERT fails, a bad pointer has been passed in. It may be
         * totally bogus, or it may have been allocated from another heap.
         * The pointer MUST come from the 'local' heap.
         */
        _ASSERTE(_CrtIsValidHeapPointer(pUserData));

I dont have access to libvlc core functions and can't try libvlc_free() to release these pointer.

This is my function :

Code: Select all

const unsigned int SistemaVLC::Proporcion(void) {
    char *Prop = NULL;
    int   Ret = 0;
    if (_MediaPlayer != NULL) {
        Prop = libvlc_video_get_aspect_ratio(_MediaPlayer);
        if (Prop == NULL)                 return IDMV_PROP_PREDETERMINADA;
        if (strcmp(Prop, "1:1") == 0)     Ret = IDMV_PROP_1_1;
        if (strcmp(Prop, "4:3") == 0)     Ret = IDMV_PROP_4_3;
        if (strcmp(Prop, "16:9") == 0)    Ret = IDMV_PROP_16_9;
        if (strcmp(Prop, "16:10") == 0)   Ret = IDMV_PROP_16_10;
        if (strcmp(Prop, "2.21:1") == 0)  Ret = IDMV_PROP_221_1;
        if (strcmp(Prop, "2.35:1") == 0)  Ret = IDMV_PROP_235_1;
        if (strcmp(Prop, "2.39:1") == 0)  Ret = IDMV_PROP_239_1;
        if (strcmp(Prop, "5:4") == 0)     Ret = IDMV_PROP_5_4;
        // En la documentacion dice que hay que liberar lo que devuelva libvlc_video_get_aspect_ratio con free() o libvlc_free()
        // Como no tenngo acceso a las funciones del core he probado la funcion free(), y esta provoca un error
        free(Prop);
    }
    return Ret;
}

Assertion callstack points to "free(Prop);"

I tried libvlc 1.1.5 and 1.1.12 on windows 7 with visual studio, and i run libvlc functions from same thread always.

Anny suggestions?

Thanks in advance for your time, and sorry for my poor english.

Posted: **12 Dec 2011 08:01**

With Visual Studio, you need to use libvlc_free().

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