FFmpeg
h274.h
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1 /*
2  * H.274 film grain synthesis
3  * Copyright (c) 2021 Niklas Haas <ffmpeg@haasn.xyz>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * H.274 film grain synthesis.
25  * @author Niklas Haas <ffmpeg@haasn.xyz>
26  */
27 
28 #ifndef AVCODEC_H274_H
29 #define AVCODEC_H274_H
30 
32 
33 // Must be initialized to {0} prior to first usage
34 typedef struct H274FilmGrainDatabase {
35  // Database of film grain patterns, lazily computed as-needed
36  int8_t db[13 /* h */][13 /* v */][64][64];
37  uint16_t residency[13 /* h */]; // bit field of v
38 
39  // Temporary buffer for slice generation
40  int16_t slice_tmp[64][64];
42 
43 /**
44  * Check whether ff_h274_apply_film_grain() supports the given parameter combination.
45  *
46  * @param model_id model_id from AVFilmGrainParams to be supplied
47  * @param pix_fmt pixel format of the frames to be supplied
48  */
49 static inline int ff_h274_film_grain_params_supported(int model_id, enum AVPixelFormat pix_fmt)
50 {
51  return model_id == 0 && pix_fmt == AV_PIX_FMT_YUV420P;
52 }
53 
54 // Synthesizes film grain on top of `in` and stores the result to `out`. `out`
55 // must already have been allocated and set to the same size and format as
56 // `in`.
57 //
58 // Returns a negative error code on error, such as invalid params.
59 // If ff_h274_film_grain_params_supported() indicated that the parameters
60 // are supported, no error will be returned if the arguments given to
61 // ff_h274_film_grain_params_supported() coincide with actual values
62 // from the frames and params.
65  const AVFilmGrainParams *params);
66 
67 #endif /* AVCODEC_H274_H */
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
out
FILE * out
Definition: movenc.c:54
ff_h274_apply_film_grain
int ff_h274_apply_film_grain(AVFrame *out, const AVFrame *in, H274FilmGrainDatabase *db, const AVFilmGrainParams *params)
Definition: h274.c:217
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:344
H274FilmGrainDatabase::slice_tmp
int16_t slice_tmp[64][64]
Definition: h274.h:40
film_grain_params.h
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demux_decode.c:41
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:73
H274FilmGrainDatabase::db
int8_t db[13][13][64][64]
Definition: h274.h:36
H274FilmGrainDatabase::residency
uint16_t residency[13]
Definition: h274.h:37
H274FilmGrainDatabase
Definition: h274.h:34
AVFilmGrainParams
This structure describes how to handle film grain synthesis in video for specific codecs.
Definition: film_grain_params.h:238
ff_h274_film_grain_params_supported
static int ff_h274_film_grain_params_supported(int model_id, enum AVPixelFormat pix_fmt)
Check whether ff_h274_apply_film_grain() supports the given parameter combination.
Definition: h274.h:49