gstreamer/subprojects/gst-plugins-bad/gst/videoparsers/gsth264parse.h
Daniel Morin 49f200cb54 h264parse: Improved AU boundary detection
- AU boundary detection reviewed to follow more closely H.264 spec. and more
  specifically clauses 7.4.1.2.3 and 7.4.1.2.4.
- The gist of the changes is a look-a-head in then next AU required identify the
  last vcl-nal of current AU and firt vcl-nal of next AU (according to
  7.4.1.2.4) followed by the identification of the first nal of next AU
  (according to 7.4.1.2.3).
- A backlog of all nals of current AU and next AU up to the point where current
  AU can identified completed is kept.
- In NAL alignement mode vcl-nal are sent immediatly but the history is kept to
  allow AU boundary detection. Non-vcl-nal can be delayed up to the reception of
  the next vcl-nal to allow a correct AUD insertion.
- Based on this improved AU boudary detection we can avoid erronous AUD
  insertion, like the one highlighted by test
  test_parse_sliced_with_prefix_and_sei_nal_au.
- Add support for MVC AU boundary detection. (H.7.4.1.2.4)
- Explicitly report SVC not supported. We don't have the SVC NAL parsing
  required to identify boundary. (missing dependency_id and quality_id fields
  from SVC, see G.7.4.1.2.4)

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5741>
2023-12-17 21:42:47 +00:00

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C

/* GStreamer H.264 Parser
* Copyright (C) <2010> Collabora ltd
* Copyright (C) <2010> Nokia Corporation
* Copyright (C) <2011> Intel Corporation
*
* Copyright (C) <2010> Mark Nauwelaerts <mark.nauwelaerts@collabora.co.uk>
* Copyright (C) <2011> Thibault Saunier <thibault.saunier@collabora.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_H264_PARSE_H__
#define __GST_H264_PARSE_H__
#include <gst/gst.h>
#include <gst/base/gstbaseparse.h>
#include <gst/codecparsers/gsth264parser.h>
#include <gst/video/video.h>
#include "gstvideoparseutils.h"
G_BEGIN_DECLS
typedef struct _H264Params H264Params;
#define GST_TYPE_H264_PARSE \
(gst_h264_parse_get_type())
#define GST_H264_PARSE(obj) \
(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_H264_PARSE,GstH264Parse))
#define GST_H264_PARSE_CLASS(klass) \
(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_H264_PARSE,GstH264ParseClass))
#define GST_IS_H264_PARSE(obj) \
(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_H264_PARSE))
#define GST_IS_H264_PARSE_CLASS(klass) \
(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_H264_PARSE))
GType gst_h264_parse_get_type (void);
typedef struct
{
gboolean valid;
guint16 frame_num;
guint8 field_pic_flag;
guint8 bottom_field_flag;
guint16 idr_pic_id;
gint32 delta_pic_order_cnt[2];
guint16 pic_order_cnt_lsb;
guint32 delta_pic_order_cnt_bottom;
guint32 first_mb_in_slice;
} GstH264ParseHistorySlice;
typedef struct
{
guint16 ref_idc;
guint8 idr_pic_flag;
/* For MVC Extension */
guint16 view_id;
} GstH264ParseHistoryNalUnit;
typedef struct
{
guint8 pic_order_cnt_type;
guint8 profile_idc;
} GstH264ParseHistorySPS;
typedef struct
{
gint id;
} GstH264ParseHistoryPPS;
typedef struct _GstH264Parse GstH264Parse;
typedef struct _GstH264ParseClass GstH264ParseClass;
struct _GstH264Parse
{
GstBaseParse baseparse;
/* stream */
gint width, height;
gint fps_num, fps_den;
gint upstream_par_n, upstream_par_d;
gint parsed_par_n, parsed_par_d;
gint parsed_fps_n, parsed_fps_d;
GstVideoColorimetry parsed_colorimetry;
/* current codec_data in output caps, if any */
GstBuffer *codec_data;
/* input codec_data, if any */
GstBuffer *codec_data_in;
guint nal_length_size;
gboolean packetized;
gboolean split_packetized;
gboolean transform;
/* state */
GstH264NalParser *nalparser;
guint state;
guint in_align;
guint align;
guint format;
gint current_off;
/* True if input format and alignment match negotiated output */
gboolean can_passthrough;
GstClockTime last_report;
gboolean push_codec;
/* The following variables have a meaning in context of "have
* SPS/PPS to push downstream", e.g. to update caps */
gboolean have_sps;
gboolean have_pps;
/* per frame sps/pps check for periodic push codec decision */
gboolean have_sps_in_frame;
gboolean have_pps_in_frame;
/* per frame AU Delimiter check used when in_format == avc or avc3 */
gboolean have_aud_in_frame;
/* tracing state whether h264parse needs to insert AUD or not.
* Used when in_format == byte-stream */
gboolean aud_needed;
/* For insertion of AU Delimiter */
gboolean aud_insert;
gboolean first_frame;
/* collected SPS and PPS NALUs */
GstBuffer *sps_nals[GST_H264_MAX_SPS_COUNT];
GstBuffer *pps_nals[GST_H264_MAX_PPS_COUNT];
/* collected SEI timestamps */
guint num_clock_timestamp;
GstH264PicTiming pic_timing_sei;
/* Infos we need to keep track of */
guint32 sei_cpb_removal_delay;
guint8 sei_pic_struct;
guint8 sei_pic_struct_pres_flag;
guint field_pic_flag;
gboolean ignore_vui_fps;
/* cached timestamps */
/* (trying to) track upstream dts and interpolate */
GstClockTime dts;
/* dts at start of last buffering period */
GstClockTime ts_trn_nb;
gboolean do_ts;
gboolean discont;
gboolean marker;
/* frame parsing */
/*guint last_nal_pos;*/
/*guint next_sc_pos;*/
gint idr_pos, sei_pos;
gint pic_timing_sei_pos;
gint pic_timing_sei_size;
gboolean update_caps;
GstAdapter *frame_out;
gboolean keyframe;
gboolean predicted;
gboolean bidirectional;
gboolean header;
gboolean frame_start;
/* AU state */
gboolean picture_start;
/* props */
gint interval;
gboolean update_timecode;
GstClockTime pending_key_unit_ts;
GstEvent *force_key_unit_event;
/* Stereo / multiview info */
GstVideoMultiviewMode multiview_mode;
GstVideoMultiviewFlags multiview_flags;
gboolean first_in_bundle;
/* For insertion of AU Delimiter */
GArray *nal_backlog;
/* Index of last vcl nal of current AU in backlog */
gint bl_curr_au_last_vcl;
/* Index of first vcl nal of next AU in backlog */
gint bl_next_au_first_vcl;
/* Index of first nal of next AU in backlog */
gint bl_next_au_first_nal;
/* Index of next nal to be processed in backlog */
gint bl_next_nal;
GstVideoParseUserData user_data;
GstVideoParseUserDataUnregistered user_data_unregistered;
GstVideoMasteringDisplayInfo mastering_display_info;
guint mastering_display_info_state;
GstVideoContentLightLevel content_light_level;
guint content_light_level_state;
/* For forward predicted trickmode */
gboolean discard_bidirectional;
/* First VCL NAL unit of primary code picuture detection context */
GstH264ParseHistorySlice history_slice[2];
GstH264ParseHistoryNalUnit history_nalu[2];
GstH264ParseHistorySPS history_sps[2];
GstH264ParseHistoryPPS history_pps[2];
};
struct _GstH264ParseClass
{
GstBaseParseClass parent_class;
};
G_END_DECLS
#endif