From 18e3d61e9e3b52c177aa7a1f2a054a8a753e1b09 Mon Sep 17 00:00:00 2001
From: Vittorio Giovara <vittorio.giovara@gmail.com>
Date: Wed, 2 Jul 2014 11:58:19 -0400
Subject: [PATCH] h264: parse display orientation SEI message

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
---
 libavcodec/h264.c     | 15 +++++++++++++++
 libavcodec/h264.h     |  8 ++++++++
 libavcodec/h264_sei.c | 22 ++++++++++++++++++++++
 3 files changed, 45 insertions(+)

diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index a04839c9c0..ec14caa30d 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -26,6 +26,7 @@
  */
 
 #include "libavutil/avassert.h"
+#include "libavutil/display.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/stereo3d.h"
 #include "libavutil/timer.h"
@@ -822,6 +823,20 @@ static void decode_postinit(H264Context *h, int setup_finished)
             stereo->flags = AV_STEREO3D_FLAG_INVERT;
     }
 
+    if (h->sei_display_orientation_present &&
+        (h->sei_anticlockwise_rotation || h->sei_hflip || h->sei_vflip)) {
+        double angle = h->sei_anticlockwise_rotation * 360 / (double) (1 << 16);
+        AVFrameSideData *rotation = av_frame_new_side_data(&cur->f,
+                                                           AV_FRAME_DATA_DISPLAYMATRIX,
+                                                           sizeof(int32_t) * 9);
+        if (!rotation)
+            return;
+
+        av_display_rotation_set((int32_t *)rotation->data, angle);
+        av_display_matrix_flip((int32_t *)rotation->data,
+                               h->sei_vflip, h->sei_hflip);
+    }
+
     // FIXME do something with unavailable reference frames
 
     /* Sort B-frames into display order */
diff --git a/libavcodec/h264.h b/libavcodec/h264.h
index 3e99832571..39023dab63 100644
--- a/libavcodec/h264.h
+++ b/libavcodec/h264.h
@@ -132,6 +132,7 @@ typedef enum {
     SEI_TYPE_USER_DATA_UNREGISTERED = 5,   ///< unregistered user data
     SEI_TYPE_RECOVERY_POINT         = 6,   ///< recovery point (frame # to decoder sync)
     SEI_TYPE_FRAME_PACKING          = 45,  ///< frame packing arrangement
+    SEI_TYPE_DISPLAY_ORIENTATION    = 47,  ///< display orientation
 } SEI_Type;
 
 /**
@@ -633,6 +634,13 @@ typedef struct H264Context {
     int content_interpretation_type;
     int quincunx_subsampling;
 
+    /**
+     * display orientation SEI message
+     */
+    int sei_display_orientation_present;
+    int sei_anticlockwise_rotation;
+    int sei_hflip, sei_vflip;
+
     /**
      * Bit set of clock types for fields/frames in picture timing SEI message.
      * For each found ct_type, appropriate bit is set (e.g., bit 1 for
diff --git a/libavcodec/h264_sei.c b/libavcodec/h264_sei.c
index 6fca2c32a9..33230b7dfa 100644
--- a/libavcodec/h264_sei.c
+++ b/libavcodec/h264_sei.c
@@ -41,6 +41,7 @@ void ff_h264_reset_sei(H264Context *h)
     h->sei_cpb_removal_delay        = -1;
     h->sei_buffering_period_present =  0;
     h->sei_frame_packing_present    =  0;
+    h->sei_display_orientation_present = 0;
 }
 
 static int decode_picture_timing(H264Context *h)
@@ -199,6 +200,22 @@ static int decode_frame_packing_arrangement(H264Context *h)
     return 0;
 }
 
+static int decode_display_orientation(H264Context *h)
+{
+    h->sei_display_orientation_present = !get_bits1(&h->gb);
+
+    if (h->sei_display_orientation_present) {
+        h->sei_hflip = get_bits1(&h->gb);     // hor_flip
+        h->sei_vflip = get_bits1(&h->gb);     // ver_flip
+
+        h->sei_anticlockwise_rotation = get_bits(&h->gb, 16);
+        get_ue_golomb(&h->gb);  // display_orientation_repetition_period
+        skip_bits1(&h->gb);     // display_orientation_extension_flag
+    }
+
+    return 0;
+}
+
 int ff_h264_decode_sei(H264Context *h)
 {
     while (get_bits_left(&h->gb) > 16) {
@@ -246,6 +263,11 @@ int ff_h264_decode_sei(H264Context *h)
             if (ret < 0)
                 return ret;
             break;
+        case SEI_TYPE_DISPLAY_ORIENTATION:
+            ret = decode_display_orientation(h);
+            if (ret < 0)
+                return ret;
+            break;
         default:
             av_log(h->avctx, AV_LOG_DEBUG, "unknown SEI type %d\n", type);
             skip_bits(&h->gb, 8 * size);