/src/ffmpeg/libswscale/graph.h

Source
/*
 * Copyright (C) 2024 Niklas Haas
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef SWSCALE_GRAPH_H
#define SWSCALE_GRAPH_H

#include <stdbool.h>

#include "libavutil/slicethread.h"
#include "libavutil/buffer.h"

#include "swscale.h"
#include "format.h"

static av_always_inline av_const int ff_fmt_vshift(enum AVPixelFormat fmt, int plane)
{
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
    return (plane == 1 || plane == 2) ? desc->log2_chroma_h : 0;
}

typedef struct SwsPass  SwsPass;
typedef struct SwsGraph SwsGraph;

/**
 * Output `h` lines of filtered data. `out` and `in` point to the
 * start of the image buffer for this pass.
 */
typedef void (*SwsPassFunc)(const SwsFrame *out, const SwsFrame *in,
                            int y, int h, const SwsPass *pass);

/**
 * Function to run from the main thread before processing any lines.
 */
typedef int (*SwsPassSetup)(const SwsFrame *out, const SwsFrame *in,
                            const SwsPass *pass);

/**
 * Represents an output buffer for a filter pass. During filter graph
 * construction, these merely hold the metadata. Allocation of the underlying
 * storage is deferred until after all filter passes are settled.
 */
typedef struct SwsPassBuffer {
    SwsFrame frame;

    int width, height; /* dimensions of this buffer */
    AVFrame *avframe;  /* backing storage for `frame` */
} SwsPassBuffer;

/**
 * Represents a single filter pass in the scaling graph. Each filter will
 * read from some previous pass's output, and write to a buffer associated
 * with the pass (or into the final output image).
 */
struct SwsPass {
    const SwsGraph *graph;

    /**
     * Filter main execution function. Called from multiple threads, with
     * the granularity dictated by `slice_h`. Individual slices sent to `run`
     * are always equal to (or smaller than, for the last slice) `slice_h`.
     */
    SwsPassFunc run;
    enum AVPixelFormat format; /* new pixel format */
    int width, height; /* new output size */
    int slice_h;       /* filter granularity */
    int num_slices;

    /**
     * Filter input. This pass's output will be resolved to form this pass's.
     * input. If NULL, the original input image is used.
     */
    SwsPass *input;

    /**
     * Filter output buffer. This struct is always allocated.
     */
    SwsPassBuffer *output; /* refstruct */

    /**
     * Called once from the main thread before running the filter. Optional.
     * Returns 0 or a negative error code.
     */
    SwsPassSetup setup;

    /**
     * Optional private state and associated free() function.
     */
    void (*free)(void *priv);
    void *priv;
};

/**
 * Filter graph, which represents a 'baked' pixel format conversion.
 */
typedef struct SwsGraph {
    SwsContext *ctx;
    AVSliceThread *slicethread;
    int num_threads; /* resolved at init() time */
    bool incomplete; /* set during init() if formats had to be inferred */
    bool noop;       /* set during init() if the graph is a no-op */

    AVBufferRef *hw_frames_ref;

    /** Sorted sequence of filter passes to apply */
    SwsPass **passes;
    int num_passes;

    /**
     * Cached copy of the public options that were used to construct this
     * SwsGraph. Used only to detect when the graph needs to be reinitialized.
     */
    SwsContext opts_copy;

    /**
     * Currently active format and processing parameters.
     */
    SwsFormat src, dst;
    int field;

    /**
     * Temporary execution state inside ff_sws_graph_run(); used to pass
     * data to worker threads.
     */
    struct {
        const SwsPass *pass; /* current filter pass */
        const SwsFrame *input; /* current filter pass input/output */
        const SwsFrame *output;
    } exec;
} SwsGraph;

/**
 * Allocate and initialize the filter graph. Returns 0 or a negative error.
 */
int ff_sws_graph_create(SwsContext *ctx, const SwsFormat *dst, const SwsFormat *src,
                        int field, SwsGraph **out_graph);


/**
 * Allocate and add a new pass to the filter graph. Takes over ownership of
 * `priv`, even on failure.
 *
 * @param graph  Filter graph to add the pass to.
 * @param fmt    Pixel format of the output image.
 * @param w      Width of the output image.
 * @param h      Height of the output image.
 * @param input  Previous pass to read from, or NULL for the input image.
 * @param align  Minimum slice alignment for this pass, or 0 for no threading.
 * @param run    Filter function to run.
 * @param setup  Optional setup function to run from the main thread.
 * @param priv   Private state for the filter run function.
 * @param free   Function to free the private state.
 * @param out_pass The newly added pass will be written here on success.
 * @return 0 or a negative error code
 */
int ff_sws_graph_add_pass(SwsGraph *graph, enum AVPixelFormat fmt,
                          int width, int height, SwsPass *input,
                          int align, SwsPassFunc run, SwsPassSetup setup,
                          void *priv, void (*free)(void *priv),
                          SwsPass **out_pass);

/**
 * Remove all passes added since the given index.
 */
void ff_sws_graph_rollback(SwsGraph *graph, int since_idx);

/**
 * Uninitialize any state associate with this filter graph and free it.
 */
void ff_sws_graph_free(SwsGraph **graph);

/**
 * Update dynamic per-frame HDR metadata without requiring a full reinit.
 */
void ff_sws_graph_update_metadata(SwsGraph *graph, const SwsColor *color);

/**
 * Wrapper around ff_sws_graph_create() that reuses the existing graph if the
 * format is compatible. This will also update dynamic per-frame metadata.
 * Must be called after changing any of the fields in `ctx`, or else they will
 * have no effect.
 */
int ff_sws_graph_reinit(SwsContext *ctx, const SwsFormat *dst, const SwsFormat *src,
                        int field, SwsGraph **graph);

/**
 * Dispatch the filter graph on a single field of the given frames. Internally
 * threaded.
 */
int ff_sws_graph_run(SwsGraph *graph, const AVFrame *dst, const AVFrame *src);

#endif /* SWSCALE_GRAPH_H */

Coverage Report

Created: 2026-04-01 07:42

Line	Count	Source
1		/*
2		* Copyright (C) 2024 Niklas Haas
3		*
4		* This file is part of FFmpeg.
5		*
6		* FFmpeg is free software; you can redistribute it and/or
7		* modify it under the terms of the GNU Lesser General Public
8		* License as published by the Free Software Foundation; either
9		* version 2.1 of the License, or (at your option) any later version.
10		*
11		* FFmpeg is distributed in the hope that it will be useful,
12		* but WITHOUT ANY WARRANTY; without even the implied warranty of
13		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14		* Lesser General Public License for more details.
15		*
16		* You should have received a copy of the GNU Lesser General Public
17		* License along with FFmpeg; if not, write to the Free Software
18		* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19		*/
20
21		#ifndef SWSCALE_GRAPH_H
22		#define SWSCALE_GRAPH_H
23
24		#include <stdbool.h>
25
26		#include "libavutil/slicethread.h"
27		#include "libavutil/buffer.h"
28
29		#include "swscale.h"
30		#include "format.h"
31
32		static av_always_inline av_const int ff_fmt_vshift(enum AVPixelFormat fmt, int plane)
33	0	{
34	0	const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(fmt);
35	0	return (plane == 1 \|\| plane == 2) ? desc->log2_chroma_h : 0;
36	0	} Unexecuted instantiation: swscale.c:ff_fmt_vshift Unexecuted instantiation: utils.c:ff_fmt_vshift Unexecuted instantiation: vscale.c:ff_fmt_vshift Unexecuted instantiation: yuv2rgb.c:ff_fmt_vshift Unexecuted instantiation: alphablend.c:ff_fmt_vshift Unexecuted instantiation: format.c:ff_fmt_vshift Unexecuted instantiation: graph.c:ff_fmt_vshift Unexecuted instantiation: hscale_fast_bilinear.c:ff_fmt_vshift Unexecuted instantiation: input.c:ff_fmt_vshift Unexecuted instantiation: ops.c:ff_fmt_vshift Unexecuted instantiation: ops_backend.c:ff_fmt_vshift Unexecuted instantiation: ops_chain.c:ff_fmt_vshift Unexecuted instantiation: ops_dispatch.c:ff_fmt_vshift Unexecuted instantiation: ops_memcpy.c:ff_fmt_vshift Unexecuted instantiation: ops_optimizer.c:ff_fmt_vshift Unexecuted instantiation: options.c:ff_fmt_vshift Unexecuted instantiation: output.c:ff_fmt_vshift Unexecuted instantiation: rgb2rgb.c:ff_fmt_vshift Unexecuted instantiation: slice.c:ff_fmt_vshift Unexecuted instantiation: swscale_unscaled.c:ff_fmt_vshift Unexecuted instantiation: gamma.c:ff_fmt_vshift Unexecuted instantiation: hscale.c:ff_fmt_vshift
37
38		typedef struct SwsPass SwsPass;
39		typedef struct SwsGraph SwsGraph;
40
41		/**
42		* Output `h` lines of filtered data. `out` and `in` point to the
43		* start of the image buffer for this pass.
44		*/
45		typedef void (SwsPassFunc)(const SwsFrame out, const SwsFrame *in,
46		int y, int h, const SwsPass *pass);
47
48		/**
49		* Function to run from the main thread before processing any lines.
50		*/
51		typedef int (SwsPassSetup)(const SwsFrame out, const SwsFrame *in,
52		const SwsPass *pass);
53
54		/**
55		* Represents an output buffer for a filter pass. During filter graph
56		* construction, these merely hold the metadata. Allocation of the underlying
57		* storage is deferred until after all filter passes are settled.
58		*/
59		typedef struct SwsPassBuffer {
60		SwsFrame frame;
61
62		int width, height; /* dimensions of this buffer */
63		AVFrame avframe; / backing storage for `frame` */
64		} SwsPassBuffer;
65
66		/**
67		* Represents a single filter pass in the scaling graph. Each filter will
68		* read from some previous pass's output, and write to a buffer associated
69		* with the pass (or into the final output image).
70		*/
71		struct SwsPass {
72		const SwsGraph *graph;
73
74		/**
75		* Filter main execution function. Called from multiple threads, with
76		* the granularity dictated by `slice_h`. Individual slices sent to `run`
77		* are always equal to (or smaller than, for the last slice) `slice_h`.
78		*/
79		SwsPassFunc run;
80		enum AVPixelFormat format; /* new pixel format */
81		int width, height; /* new output size */
82		int slice_h; /* filter granularity */
83		int num_slices;
84
85		/**
86		* Filter input. This pass's output will be resolved to form this pass's.
87		* input. If NULL, the original input image is used.
88		*/
89		SwsPass *input;
90
91		/**
92		* Filter output buffer. This struct is always allocated.
93		*/
94		SwsPassBuffer output; / refstruct */
95
96		/**
97		* Called once from the main thread before running the filter. Optional.
98		* Returns 0 or a negative error code.
99		*/
100		SwsPassSetup setup;
101
102		/**
103		* Optional private state and associated free() function.
104		*/
105		void (free)(void priv);
106		void *priv;
107		};
108
109		/**
110		* Filter graph, which represents a 'baked' pixel format conversion.
111		*/
112		typedef struct SwsGraph {
113		SwsContext *ctx;
114		AVSliceThread *slicethread;
115		int num_threads; /* resolved at init() time */
116		bool incomplete; /* set during init() if formats had to be inferred */
117		bool noop; /* set during init() if the graph is a no-op */
118
119		AVBufferRef *hw_frames_ref;
120
121		/** Sorted sequence of filter passes to apply */
122		SwsPass **passes;
123		int num_passes;
124
125		/**
126		* Cached copy of the public options that were used to construct this
127		* SwsGraph. Used only to detect when the graph needs to be reinitialized.
128		*/
129		SwsContext opts_copy;
130
131		/**
132		* Currently active format and processing parameters.
133		*/
134		SwsFormat src, dst;
135		int field;
136
137		/**
138		* Temporary execution state inside ff_sws_graph_run(); used to pass
139		* data to worker threads.
140		*/
141		struct {
142		const SwsPass pass; / current filter pass */
143		const SwsFrame input; / current filter pass input/output */
144		const SwsFrame *output;
145		} exec;
146		} SwsGraph;
147
148		/**
149		* Allocate and initialize the filter graph. Returns 0 or a negative error.
150		*/
151		int ff_sws_graph_create(SwsContext ctx, const SwsFormat dst, const SwsFormat *src,
152		int field, SwsGraph **out_graph);
153
154
155		/**
156		* Allocate and add a new pass to the filter graph. Takes over ownership of
157		* `priv`, even on failure.
158		*
159		* @param graph Filter graph to add the pass to.
160		* @param fmt Pixel format of the output image.
161		* @param w Width of the output image.
162		* @param h Height of the output image.
163		* @param input Previous pass to read from, or NULL for the input image.
164		* @param align Minimum slice alignment for this pass, or 0 for no threading.
165		* @param run Filter function to run.
166		* @param setup Optional setup function to run from the main thread.
167		* @param priv Private state for the filter run function.
168		* @param free Function to free the private state.
169		* @param out_pass The newly added pass will be written here on success.
170		* @return 0 or a negative error code
171		*/
172		int ff_sws_graph_add_pass(SwsGraph *graph, enum AVPixelFormat fmt,
173		int width, int height, SwsPass *input,
174		int align, SwsPassFunc run, SwsPassSetup setup,
175		void priv, void (free)(void *priv),
176		SwsPass **out_pass);
177
178		/**
179		* Remove all passes added since the given index.
180		*/
181		void ff_sws_graph_rollback(SwsGraph *graph, int since_idx);
182
183		/**
184		* Uninitialize any state associate with this filter graph and free it.
185		*/
186		void ff_sws_graph_free(SwsGraph **graph);
187
188		/**
189		* Update dynamic per-frame HDR metadata without requiring a full reinit.
190		*/
191		void ff_sws_graph_update_metadata(SwsGraph graph, const SwsColor color);
192
193		/**
194		* Wrapper around ff_sws_graph_create() that reuses the existing graph if the
195		* format is compatible. This will also update dynamic per-frame metadata.
196		* Must be called after changing any of the fields in `ctx`, or else they will
197		* have no effect.
198		*/
199		int ff_sws_graph_reinit(SwsContext ctx, const SwsFormat dst, const SwsFormat *src,
200		int field, SwsGraph **graph);
201
202		/**
203		* Dispatch the filter graph on a single field of the given frames. Internally
204		* threaded.
205		*/
206		int ff_sws_graph_run(SwsGraph graph, const AVFrame dst, const AVFrame *src);
207
208		#endif /* SWSCALE_GRAPH_H */