ijkplayer源码---FFPlayer结构体7

Uint32 overlay_format;

我们搜索代码发现有两处赋值的地方

inline static void ffp_reset_internal(FFPlayer *ffp){
    
    ffp->overlay_format         = SDL_FCC_RV32;
}


void ffp_set_overlay_format(FFPlayer *ffp, int chroma_fourcc)
{
    switch (chroma_fourcc) {
        case SDL_FCC__GLES2:
        case SDL_FCC_I420:
        case SDL_FCC_YV12:
        case SDL_FCC_RV16:
        case SDL_FCC_RV24:
        case SDL_FCC_RV32:
            ffp->overlay_format = chroma_fourcc;
            break;
#ifdef __APPLE__
        case SDL_FCC_I444P10LE:
            ffp->overlay_format = chroma_fourcc;
            break;
#endif
        default:
            av_log(ffp, AV_LOG_ERROR, "ffp_set_overlay_format: unknown chroma fourcc: %d\n", chroma_fourcc);
            break;
    }
}

而ffp_set_overlay_format有没有调用

所以overlay_format就是SDL_FCC_RV32

#define SDL_FCC_RV32    SDL_FOURCC('R', 'V', '3', '2')    /**< bpp=32, RGBX8888 */

RGBX 一个像素四个字节

那么overlay_format又用在了什么地方呢？

static void alloc_picture(FFPlayer *ffp, int frame_format){
    SDL_VoutSetOverlayFormat(ffp->vout, ffp->overlay_format);
}

解码成功，创建picture时，设置给

SDL_Vout的overlay_format。

那么SDL_Vout的overlay_format又用在那里呢？

static int func_display_overlay_l(SDL_Vout *vout, SDL_VoutOverlay *overlay)
{
    SDL_Vout_Opaque *opaque = vout->opaque;
    ANativeWindow *native_window = opaque->native_window;

    if (!native_window) {
        if (!opaque->null_native_window_warned) {
            opaque->null_native_window_warned = 1;
            ALOGW("func_display_overlay_l: NULL native_window");
        }
        return -1;
    } else {
        opaque->null_native_window_warned = 1;
    }

    if (!overlay) {
        ALOGE("func_display_overlay_l: NULL overlay");
        return -1;
    }

    if (overlay->w <= 0 || overlay->h <= 0) {
        ALOGE("func_display_overlay_l: invalid overlay dimensions(%d, %d)", overlay->w, overlay->h);
        return -1;
    }

    switch(overlay->format) {
    case SDL_FCC__AMC: {
        // only ANativeWindow support
        IJK_EGL_terminate(opaque->egl);
        return SDL_VoutOverlayAMediaCodec_releaseFrame_l(overlay, NULL, true);
    }
    case SDL_FCC_RV24:
    case SDL_FCC_I420:
    case SDL_FCC_I444P10LE: {
        // only GLES support
        if (opaque->egl)
            return IJK_EGL_display(opaque->egl, native_window, overlay);
        break;
    }
    case SDL_FCC_YV12:
    case SDL_FCC_RV16:
    case SDL_FCC_RV32: {
        // both GLES & ANativeWindow support
        if (vout->overlay_format == SDL_FCC__GLES2 && opaque->egl)
            return IJK_EGL_display(opaque->egl, native_window, overlay);
        break;
    }
    }

    // fallback to ANativeWindow
    IJK_EGL_terminate(opaque->egl);
    return SDL_Android_NativeWindow_display_l(native_window, overlay); 
}

这时我们又发现了一个overlay->format，它和overlay_format 不是一会事

overlay->format在那里赋值呢？

通过下面一个流程图大家可以看到硬解码赋值为了

SDL_FCC__AMC