h264: decouple h264_sei from the h264 decoder

Make the SEI parsing independent of the H264Context, to allow
decoupling the parser from the decoder.

1 files changed, 137 insertions, 0 deletions

diff --git a/libavcodec/h264_sei.h b/libavcodec/h264_sei.h
new file mode 100644
index 0000000000..58f5ecc5a9
--- /dev/null
+++ b/libavcodec/h264_sei.h
@@ -0,0 +1,137 @@
+/*
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_H264_SEI_H
+#define AVCODEC_H264_SEI_H
+
+#include "get_bits.h"
+
+/**
+ * SEI message types
+ */
+typedef enum {
+    SEI_TYPE_BUFFERING_PERIOD       = 0,   ///< buffering period (H.264, D.1.1)
+    SEI_TYPE_PIC_TIMING             = 1,   ///< picture timing
+    SEI_TYPE_USER_DATA_REGISTERED   = 4,   ///< registered user data as specified by Rec. ITU-T T.35
+    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;
+
+/**
+ * pic_struct in picture timing SEI message
+ */
+typedef enum {
+    SEI_PIC_STRUCT_FRAME             = 0, ///<  0: %frame
+    SEI_PIC_STRUCT_TOP_FIELD         = 1, ///<  1: top field
+    SEI_PIC_STRUCT_BOTTOM_FIELD      = 2, ///<  2: bottom field
+    SEI_PIC_STRUCT_TOP_BOTTOM        = 3, ///<  3: top field, bottom field, in that order
+    SEI_PIC_STRUCT_BOTTOM_TOP        = 4, ///<  4: bottom field, top field, in that order
+    SEI_PIC_STRUCT_TOP_BOTTOM_TOP    = 5, ///<  5: top field, bottom field, top field repeated, in that order
+    SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM = 6, ///<  6: bottom field, top field, bottom field repeated, in that order
+    SEI_PIC_STRUCT_FRAME_DOUBLING    = 7, ///<  7: %frame doubling
+    SEI_PIC_STRUCT_FRAME_TRIPLING    = 8  ///<  8: %frame tripling
+} SEI_PicStructType;
+
+typedef struct H264SEIPictureTiming {
+    SEI_PicStructType pic_struct;
+
+    /**
+     * 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
+     * interlaced).
+     */
+    int ct_type;
+
+    /**
+     * dpb_output_delay in picture timing SEI message, see H.264 C.2.2
+     */
+    int dpb_output_delay;
+
+    /**
+     * cpb_removal_delay in picture timing SEI message, see H.264 C.1.2
+     */
+    int cpb_removal_delay;
+} H264SEIPictureTiming;
+
+typedef struct H264SEIAFD {
+    int present;
+    uint8_t active_format_description;
+} H264SEIAFD;
+
+typedef struct H264SEIA53Caption {
+    int a53_caption_size;
+    uint8_t *a53_caption;
+} H264SEIA53Caption;
+
+typedef struct H264SEIUnregistered {
+    int x264_build;
+} H264SEIUnregistered;
+
+typedef struct H264SEIRecoveryPoint {
+    /**
+     * recovery_frame_cnt
+     *
+     * Set to -1 if no recovery point SEI message found or to number of frames
+     * before playback synchronizes. Frames having recovery point are key
+     * frames.
+     */
+    int recovery_frame_cnt;
+} H264SEIRecoveryPoint;
+
+typedef struct H264SEIBufferingPeriod {
+    int present;   ///< Buffering period SEI flag
+    int initial_cpb_removal_delay[32];  ///< Initial timestamps for CPBs
+} H264SEIBufferingPeriod;
+
+typedef struct H264SEIFramePacking {
+    int present;
+    int arrangement_type;
+    int content_interpretation_type;
+    int quincunx_subsampling;
+} H264SEIFramePacking;
+
+typedef struct H264SEIDisplayOrientation {
+    int present;
+    int anticlockwise_rotation;
+    int hflip, vflip;
+} H264SEIDisplayOrientation;
+
+typedef struct H264SEIContext {
+    H264SEIPictureTiming picture_timing;
+    H264SEIAFD afd;
+    H264SEIA53Caption a53_caption;
+    H264SEIUnregistered unregistered;
+    H264SEIRecoveryPoint recovery_point;
+    H264SEIBufferingPeriod buffering_period;
+    H264SEIFramePacking frame_packing;
+    H264SEIDisplayOrientation display_orientation;
+} H264SEIContext;
+
+struct H264ParamSets;
+
+int ff_h264_sei_decode(H264SEIContext *h, GetBitContext *gb,
+                       const struct H264ParamSets *ps, void *logctx);
+
+/**
+ * Reset SEI values at the beginning of the frame.
+ */
+void ff_h264_sei_uninit(H264SEIContext *h);
+
+#endif /* AVCODEC_H264_SEI_H */