screenshot: allow taking screenshots with subtitles

This adds a new screenshot mode "subtitles", which basically takes the
video frame as decoded, and renders subtitles into it.

This may fail for some pixel formats, because libswscale sucks. If this
becomes ever a real problem, the code could be changed to convert the
image to RGBA first (or whatever the image writer wants), and then
render the subtitles into it. This would avoid the additional image
copy needed with vo_xv too. But for now, it seems better to go with the
current method in the common case: vo_opengl creates an image copy
anyway, and drawing bitmaps to yv12 is better, as no color space
conversion is involved in draw_bmp.c's up/downsampling conversion.

1 files changed, 2 insertions, 7 deletions

diff --git a/screenshot.h b/screenshot.h
index 6d205990f8..01dd372aa2 100644
--- a/screenshot.h
+++ b/screenshot.h
@@ -22,7 +22,6 @@
 #include <stdbool.h>
 
 struct MPContext;
-struct mp_image;
 
 // One time initialization at program start.
 void screenshot_init(struct MPContext *mpctx);
@@ -30,13 +29,9 @@ void screenshot_init(struct MPContext *mpctx);
 // Request a taking & saving a screenshot of the currently displayed frame.
 // each_frame: If set, this toggles per-frame screenshots, exactly like the
 //             screenshot slave command (MP_CMD_SCREENSHOT).
-// full_window: If set, save the actual output window contents.
+// mode: 0: -, 1: save the actual output window contents, 2: with subtitles.
 void screenshot_request(struct MPContext *mpctx, bool each_frame,
-                        bool full_window);
-
-// Save the screenshot contained in the image to disk.
-// The image can be in any format supported by libswscale.
-void screenshot_save(struct MPContext *mpctx, struct mp_image *image);
+                        int mode);
 
 // Called by the playback core code when a new frame is displayed.
 void screenshot_flip(struct MPContext *mpctx);