vd_lavc: add DR1 support

Replace libavcodec's native buffer allocation with code taken from
ffplay/ffmpeg's libavfilter support. The code in lavc_dr1.c is directly
copied from cmdutils.c. Note that this is quite arcane code, which
contains some workarounds for decoder bugs and the like. This is not
really a maintainance burden, since fixes from ffmpeg can be directly
applied to the code in lavc_dr1.c.

It's unknown why libavcodec doesn't provide such a function directly.
avcodec_default_get_buffer() can't be reused for various reasons.
There's some hope that the work known as The Evil Plan [1] will make
custom get_buffer implementations unneeded.

The DR1 support as of this commit does nothing. A future commit will
use it to implement ref-counting for mp_image (similar to how AVFrame
will be ref-counted with The Evil Plan.)

[1] http://lists.libav.org/pipermail/libav-devel/2012-December/039781.html

1 files changed, 41 insertions, 0 deletions

diff --git a/video/decode/lavc.h b/video/decode/lavc.h
new file mode 100644
index 0000000000..bf8a3fc12c
--- /dev/null
+++ b/video/decode/lavc.h
@@ -0,0 +1,41 @@
+#ifndef MPV_LAVC_H
+#define MPV_LAVC_H
+
+#include <libavcodec/avcodec.h>
+
+#include "demux/stheader.h"
+#include "video/mp_image.h"
+
+#define MAX_NUM_MPI 50
+
+typedef struct ffmpeg_ctx {
+    AVCodecContext *avctx;
+    AVFrame *pic;
+    struct mp_image export_mpi;
+    struct mp_image hwdec_mpi[MAX_NUM_MPI];
+    struct hwdec *hwdec;
+    enum PixelFormat pix_fmt;
+    int do_dr1;
+    int vo_initialized;
+    int best_csp;
+    int qp_stat[32];
+    double qp_sum;
+    double inv_qp_sum;
+    AVRational last_sample_aspect_ratio;
+    enum AVDiscard skip_frame;
+    int rawvideo_fmt;
+    AVCodec *software_fallback;
+    struct FramePool *dr1_buffer_pool;
+} vd_ffmpeg_ctx;
+
+int mp_codec_get_buffer(AVCodecContext *s, AVFrame *frame);
+void mp_codec_release_buffer(AVCodecContext *s, AVFrame *frame);
+
+struct FrameBuffer;
+
+void mp_buffer_ref(struct FrameBuffer *buffer);
+void mp_buffer_unref(struct FrameBuffer *buffer);
+
+void mp_buffer_pool_free(struct FramePool **pool);
+
+#endif