When rendering a PGS window area where the left edge is not at
pixel 0, the chroma was being rendered in the wrong place since
commit 4dc648d3430b67592cf1413ccef415f70889d71e
Refactor the DVD subpicture compositing, switching it to 8-bit alpha
calculations. Reuse some of the resulting code to implement PGS
subpicture blending.
Implement parsing and collecting of composition objects properly, but
assuming a single active window and colour palette for now. I need more
PGS samples.
Original commit message from CVS:
* gst/dvdspu/gstdvdspu-render.c: (gst_dvd_spu_render_spu):
* gst/dvdspu/gstdvdspu.c: (dvdspu_debug), (GST_CAT_DEFAULT),
(subpic_sink_factory), (gst_dvd_spu_base_init),
(gst_dvd_spu_class_init), (gst_dvd_spu_init), (gst_dvd_spu_clear),
(gst_dvd_spu_dispose), (gst_dvd_spu_finalize),
(gst_dvd_spu_flush_spu_info), (gst_dvd_spu_buffer_alloc),
(gst_dvd_spu_src_event), (gst_dvd_spu_video_set_caps),
(gst_dvd_spu_video_proxy_getcaps), (gst_dvd_spu_video_event),
(gst_dvd_spu_video_chain), (dvspu_handle_vid_buffer),
(gst_dvd_spu_redraw_still), (gst_dvd_spu_parse_chg_colcon),
(gst_dvd_spu_exec_cmd_blk), (gst_dvd_spu_finish_spu_buf),
(gst_dvd_spu_setup_cmd_blk), (gst_dvd_spu_handle_new_spu_buf),
(gst_dvd_spu_handle_dvd_event), (gst_dvd_spu_advance_spu),
(gst_dvd_spu_check_still_updates), (gst_dvd_spu_subpic_chain),
(gst_dvd_spu_subpic_event), (gst_dvd_spu_change_state),
(gst_dvd_spu_plugin_init):
* gst/dvdspu/gstdvdspu.h: (GST_TYPE_DVD_SPU):
Fix up dvdspu element again after previous namespace mangling:
rename debug category variable to old name, matching that in
dvdspu-render.c, to avoid undefined symbol error when loading
the module; same for the _render function in dvdspu-render.c:
we must use the same name in both .c files; change functions
now called gstgst_* back to gst_* again; and while we're at it,
we may as well canonicalise the namespace properly, namely to
gst_dvd_spu_*.
