vo_corevideo: add screenshot capability

Added screenshot capability to the corevideo VO by sending back the raw data
from the CVPixelBuffer.

Also added "screenshot window" functionality from the other OpenGL based VOs,
which uses glReadPixels to read image data back. This was moved to gl_common to
avoid duplication.

1 files changed, 48 insertions, 0 deletions

diff --git a/libvo/vo_corevideo.m b/libvo/vo_corevideo.m
index 06010cad49..fb9350cc47 100644
--- a/libvo/vo_corevideo.m
+++ b/libvo/vo_corevideo.m
@@ -344,6 +344,46 @@ static void set_yuv_colorspace(struct vo *vo)
     vo->want_redraw = true;
 }
 
+static int get_image_fmt(struct vo *vo)
+{
+    struct priv *p = vo->priv;
+    switch (p->pixelFormat) {
+        case kYUVSPixelFormat:   return IMGFMT_YUY2;
+        case k24RGBPixelFormat:  return IMGFMT_RGB24;
+        case k32ARGBPixelFormat: return IMGFMT_ARGB;
+        case k32BGRAPixelFormat: return IMGFMT_BGRA;
+    }
+    mp_msg(MSGT_VO, MSGL_ERR, "[vo_corevideo] Failed to convert pixel format. "
+        "Please contact the developers. PixelFormat: %d\n", p->pixelFormat);
+    return -1;
+}
+
+static mp_image_t *get_screenshot(struct vo *vo)
+{
+    int img_fmt = get_image_fmt(vo);
+    if (img_fmt < 0) return NULL;
+
+    struct priv *p = vo->priv;
+    void *base = CVPixelBufferGetBaseAddress(p->pixelBuffer);
+
+    size_t width      = CVPixelBufferGetWidth(p->pixelBuffer);
+    size_t height     = CVPixelBufferGetHeight(p->pixelBuffer);
+    size_t stride     = CVPixelBufferGetBytesPerRow(p->pixelBuffer);
+    size_t image_size = stride * height;
+
+    mp_image_t *image = alloc_mpi(width, height, img_fmt);
+    memcpy(image->planes[0], base, image_size);
+    image->stride[0]  = stride;
+
+    image->width  = width;
+    image->height = height;
+
+    image->w = vo->aspdat.prew;
+    image->h = vo->aspdat.preh;
+
+    return image;
+}
+
 static int control(struct vo *vo, uint32_t request, void *data)
 {
     struct priv *p = vo->priv;
@@ -377,6 +417,14 @@ static int control(struct vo *vo, uint32_t request, void *data)
         case VOCTRL_GET_YUV_COLORSPACE:
             *(struct mp_csp_details *)data = p->colorspace;
             return VO_TRUE;
+        case VOCTRL_SCREENSHOT: {
+            struct voctrl_screenshot_args *args = data;
+            if (args->full_window)
+                args->out_image = glGetWindowScreenshot(p->mpglctx->gl);
+            else
+                args->out_image = get_screenshot(vo);
+            return VO_TRUE;
+        }
     }
     return VO_NOTIMPL;
 }