[deb_ffmpeg.git] / ffmpeg / libavfilter / formats.h

/*
 * 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 AVFILTER_FORMATS_H
#define AVFILTER_FORMATS_H

#include "avfilter.h"

/**
 * A list of supported formats for one end of a filter link. This is used
 * during the format negotiation process to try to pick the best format to
 * use to minimize the number of necessary conversions. Each filter gives a
 * list of the formats supported by each input and output pad. The list
 * given for each pad need not be distinct - they may be references to the
 * same list of formats, as is often the case when a filter supports multiple
 * formats, but will always output the same format as it is given in input.
 *
 * In this way, a list of possible input formats and a list of possible
 * output formats are associated with each link. When a set of formats is
 * negotiated over a link, the input and output lists are merged to form a
 * new list containing only the common elements of each list. In the case
 * that there were no common elements, a format conversion is necessary.
 * Otherwise, the lists are merged, and all other links which reference
 * either of the format lists involved in the merge are also affected.
 *
 * For example, consider the filter chain:
 * filter (a) --> (b) filter (b) --> (c) filter
 *
 * where the letters in parenthesis indicate a list of formats supported on
 * the input or output of the link. Suppose the lists are as follows:
 * (a) = {A, B}
 * (b) = {A, B, C}
 * (c) = {B, C}
 *
 * First, the first link's lists are merged, yielding:
 * filter (a) --> (a) filter (a) --> (c) filter
 *
 * Notice that format list (b) now refers to the same list as filter list (a).
 * Next, the lists for the second link are merged, yielding:
 * filter (a) --> (a) filter (a) --> (a) filter
 *
 * where (a) = {B}.
 *
 * Unfortunately, when the format lists at the two ends of a link are merged,
 * we must ensure that all links which reference either pre-merge format list
 * get updated as well. Therefore, we have the format list structure store a
 * pointer to each of the pointers to itself.
 */
struct AVFilterFormats {
    unsigned nb_formats;        ///< number of formats
    int *formats;               ///< list of media formats

    unsigned refcount;          ///< number of references to this list
    struct AVFilterFormats ***refs; ///< references to this list
};

/**
 * A list of supported channel layouts.
 *
 * The list works the same as AVFilterFormats, except for the following
 * differences:
 * - A list with all_layouts = 1 means all channel layouts with a known
 *   disposition; nb_channel_layouts must then be 0.
 * - A list with all_counts = 1 means all channel counts, with a known or
 *   unknown disposition; nb_channel_layouts must then be 0 and all_layouts 1.
 * - The list must not contain a layout with a known disposition and a
 *   channel count with unknown disposition with the same number of channels
 *   (e.g. AV_CH_LAYOUT_STEREO and FF_COUNT2LAYOUT(2).
 */
typedef struct AVFilterChannelLayouts {
    uint64_t *channel_layouts;  ///< list of channel layouts
    int    nb_channel_layouts;  ///< number of channel layouts
    char all_layouts;           ///< accept any known channel layout
    char all_counts;            ///< accept any channel layout or count

    unsigned refcount;          ///< number of references to this list
    struct AVFilterChannelLayouts ***refs; ///< references to this list
} AVFilterChannelLayouts;

/**
 * Encode a channel count as a channel layout.
 * FF_COUNT2LAYOUT(c) means any channel layout with c channels, with a known
 * or unknown disposition.
 * The result is only valid inside AVFilterChannelLayouts and immediately
 * related functions.
 */
#define FF_COUNT2LAYOUT(c) (0x8000000000000000ULL | (c))

/**
 * Decode a channel count encoded as a channel layout.
 * Return 0 if the channel layout was a real one.
 */
#define FF_LAYOUT2COUNT(l) (((l) & 0x8000000000000000ULL) ? \
                           (int)((l) & 0x7FFFFFFF) : 0)

/**
 * Return a channel layouts/samplerates list which contains the intersection of
 * the layouts/samplerates of a and b. Also, all the references of a, all the
 * references of b, and a and b themselves will be deallocated.
 *
 * If a and b do not share any common elements, neither is modified, and NULL
 * is returned.
 */
AVFilterChannelLayouts *ff_merge_channel_layouts(AVFilterChannelLayouts *a,
                                                 AVFilterChannelLayouts *b);
AVFilterFormats *ff_merge_samplerates(AVFilterFormats *a,
                                      AVFilterFormats *b);

/**
 * Construct an empty AVFilterChannelLayouts/AVFilterFormats struct --
 * representing any channel layout (with known disposition)/sample rate.
 */
AVFilterChannelLayouts *ff_all_channel_layouts(void);
AVFilterFormats *ff_all_samplerates(void);

/**
 * Construct an AVFilterChannelLayouts coding for any channel layout, with
 * known or unknown disposition.
 */
AVFilterChannelLayouts *ff_all_channel_counts(void);

AVFilterChannelLayouts *avfilter_make_format64_list(const int64_t *fmts);


/**
 * A helper for query_formats() which sets all links to the same list of channel
 * layouts/sample rates. If there are no links hooked to this filter, the list
 * is freed.
 */
void ff_set_common_channel_layouts(AVFilterContext *ctx,
                                   AVFilterChannelLayouts *layouts);
void ff_set_common_samplerates(AVFilterContext *ctx,
                               AVFilterFormats *samplerates);

/**
 * A helper for query_formats() which sets all links to the same list of
 * formats. If there are no links hooked to this filter, the list of formats is
 * freed.
 */
void ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats);

int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout);

/**
 * Add *ref as a new reference to f.
 */
void ff_channel_layouts_ref(AVFilterChannelLayouts *f,
                            AVFilterChannelLayouts **ref);

/**
 * Remove a reference to a channel layouts list.
 */
void ff_channel_layouts_unref(AVFilterChannelLayouts **ref);

void ff_channel_layouts_changeref(AVFilterChannelLayouts **oldref,
                                  AVFilterChannelLayouts **newref);

int ff_default_query_formats(AVFilterContext *ctx);

/**
 * Set the formats list to all existing formats.
 * This function behaves like ff_default_query_formats(), except it also
 * accepts channel layouts with unknown disposition. It should only be used
 * with audio filters.
 */
int ff_query_formats_all(AVFilterContext *ctx);


/**
 * Create a list of supported formats. This is intended for use in
 * AVFilter->query_formats().
 *
 * @param fmts list of media formats, terminated by -1
 * @return the format list, with no existing references
 */
AVFilterFormats *ff_make_format_list(const int *fmts);

/**
 * Add fmt to the list of media formats contained in *avff.
 * If *avff is NULL the function allocates the filter formats struct
 * and puts its pointer in *avff.
 *
 * @return a non negative value in case of success, or a negative
 * value corresponding to an AVERROR code in case of error
 */
int ff_add_format(AVFilterFormats **avff, int64_t fmt);

/**
 * Return a list of all formats supported by FFmpeg for the given media type.
 */
AVFilterFormats *ff_all_formats(enum AVMediaType type);

/**
 * Construct a formats list containing all planar sample formats.
 */
AVFilterFormats *ff_planar_sample_fmts(void);

/**
 * Return a format list which contains the intersection of the formats of
 * a and b. Also, all the references of a, all the references of b, and
 * a and b themselves will be deallocated.
 *
 * If a and b do not share any common formats, neither is modified, and NULL
 * is returned.
 */
AVFilterFormats *ff_merge_formats(AVFilterFormats *a, AVFilterFormats *b,
                                  enum AVMediaType type);

/**
 * Add *ref as a new reference to formats.
 * That is the pointers will point like in the ascii art below:
 *   ________
 *  |formats |<--------.
 *  |  ____  |     ____|___________________
 *  | |refs| |    |  __|_
 *  | |* * | |    | |  | |  AVFilterLink
 *  | |* *--------->|*ref|
 *  | |____| |    | |____|
 *  |________|    |________________________
 */
void ff_formats_ref(AVFilterFormats *formats, AVFilterFormats **ref);

/**
 * If *ref is non-NULL, remove *ref as a reference to the format list
 * it currently points to, deallocates that list if this was the last
 * reference, and sets *ref to NULL.
 *
 *         Before                                 After
 *   ________                               ________         NULL
 *  |formats |<--------.                   |formats |         ^
 *  |  ____  |     ____|________________   |  ____  |     ____|________________
 *  | |refs| |    |  __|_                  | |refs| |    |  __|_
 *  | |* * | |    | |  | |  AVFilterLink   | |* * | |    | |  | |  AVFilterLink
 *  | |* *--------->|*ref|                 | |*   | |    | |*ref|
 *  | |____| |    | |____|                 | |____| |    | |____|
 *  |________|    |_____________________   |________|    |_____________________
 */
void ff_formats_unref(AVFilterFormats **ref);

/**
 *
 *         Before                                 After
 *   ________                         ________
 *  |formats |<---------.            |formats |<---------.
 *  |  ____  |       ___|___         |  ____  |       ___|___
 *  | |refs| |      |   |   |        | |refs| |      |   |   |   NULL
 *  | |* *--------->|*oldref|        | |* *--------->|*newref|     ^
 *  | |* * | |      |_______|        | |* * | |      |_______|  ___|___
 *  | |____| |                       | |____| |                |   |   |
 *  |________|                       |________|                |*oldref|
 *                                                             |_______|
 */
void ff_formats_changeref(AVFilterFormats **oldref, AVFilterFormats **newref);

#endif /* AVFILTER_FORMATS_H */
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* This file is part of FFmpeg.
	3	*
	4	* FFmpeg is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU Lesser General Public
	6	* License as published by the Free Software Foundation; either
	7	* version 2.1 of the License, or (at your option) any later version.
	8	*
	9	* FFmpeg is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	* Lesser General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU Lesser General Public
	15	* License along with FFmpeg; if not, write to the Free Software
	16	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	17	*/
	18
	19	#ifndef AVFILTER_FORMATS_H
	20	#define AVFILTER_FORMATS_H
	21
	22	#include "avfilter.h"
	23
	24	/**
	25	* A list of supported formats for one end of a filter link. This is used
	26	* during the format negotiation process to try to pick the best format to
	27	* use to minimize the number of necessary conversions. Each filter gives a
	28	* list of the formats supported by each input and output pad. The list
	29	* given for each pad need not be distinct - they may be references to the
	30	* same list of formats, as is often the case when a filter supports multiple
	31	* formats, but will always output the same format as it is given in input.
	32	*
	33	* In this way, a list of possible input formats and a list of possible
	34	* output formats are associated with each link. When a set of formats is
	35	* negotiated over a link, the input and output lists are merged to form a
	36	* new list containing only the common elements of each list. In the case
	37	* that there were no common elements, a format conversion is necessary.
	38	* Otherwise, the lists are merged, and all other links which reference
	39	* either of the format lists involved in the merge are also affected.
	40	*
	41	* For example, consider the filter chain:
	42	* filter (a) --> (b) filter (b) --> (c) filter
	43	*
	44	* where the letters in parenthesis indicate a list of formats supported on
	45	* the input or output of the link. Suppose the lists are as follows:
	46	* (a) = {A, B}
	47	* (b) = {A, B, C}
	48	* (c) = {B, C}
	49	*
	50	* First, the first link's lists are merged, yielding:
	51	* filter (a) --> (a) filter (a) --> (c) filter
	52	*
	53	* Notice that format list (b) now refers to the same list as filter list (a).
	54	* Next, the lists for the second link are merged, yielding:
	55	* filter (a) --> (a) filter (a) --> (a) filter
	56	*
	57	* where (a) = {B}.
	58	*
	59	* Unfortunately, when the format lists at the two ends of a link are merged,
	60	* we must ensure that all links which reference either pre-merge format list
	61	* get updated as well. Therefore, we have the format list structure store a
	62	* pointer to each of the pointers to itself.
	63	*/
	64	struct AVFilterFormats {
65	unsigned nb_formats; ///< number of formats
66	int *formats; ///< list of media formats
67
68	unsigned refcount; ///< number of references to this list
69	struct AVFilterFormats ***refs; ///< references to this list
70	};
71
72	/**
73	* A list of supported channel layouts.
74	*
75	* The list works the same as AVFilterFormats, except for the following
76	* differences:
77	* - A list with all_layouts = 1 means all channel layouts with a known
78	* disposition; nb_channel_layouts must then be 0.
79	* - A list with all_counts = 1 means all channel counts, with a known or
80	* unknown disposition; nb_channel_layouts must then be 0 and all_layouts 1.
81	* - The list must not contain a layout with a known disposition and a
82	* channel count with unknown disposition with the same number of channels
83	* (e.g. AV_CH_LAYOUT_STEREO and FF_COUNT2LAYOUT(2).
84	*/
85	typedef struct AVFilterChannelLayouts {
86	uint64_t *channel_layouts; ///< list of channel layouts
87	int nb_channel_layouts; ///< number of channel layouts
88	char all_layouts; ///< accept any known channel layout
89	char all_counts; ///< accept any channel layout or count
90
91	unsigned refcount; ///< number of references to this list
92	struct AVFilterChannelLayouts ***refs; ///< references to this list
93	} AVFilterChannelLayouts;
94
95	/**
96	* Encode a channel count as a channel layout.
97	* FF_COUNT2LAYOUT(c) means any channel layout with c channels, with a known
98	* or unknown disposition.
99	* The result is only valid inside AVFilterChannelLayouts and immediately
100	* related functions.
101	*/
102	#define FF_COUNT2LAYOUT(c) (0x8000000000000000ULL \| (c))
103
104	/**
105	* Decode a channel count encoded as a channel layout.
106	* Return 0 if the channel layout was a real one.
107	*/
108	#define FF_LAYOUT2COUNT(l) (((l) & 0x8000000000000000ULL) ? \
109	(int)((l) & 0x7FFFFFFF) : 0)
110
111	/**
112	* Return a channel layouts/samplerates list which contains the intersection of
113	* the layouts/samplerates of a and b. Also, all the references of a, all the
114	* references of b, and a and b themselves will be deallocated.
115	*
116	* If a and b do not share any common elements, neither is modified, and NULL
117	* is returned.
118	*/
119	AVFilterChannelLayouts ff_merge_channel_layouts(AVFilterChannelLayouts a,
120	AVFilterChannelLayouts *b);
121	AVFilterFormats ff_merge_samplerates(AVFilterFormats a,
122	AVFilterFormats *b);
123
124	/**
125	* Construct an empty AVFilterChannelLayouts/AVFilterFormats struct --
126	* representing any channel layout (with known disposition)/sample rate.
127	*/
128	AVFilterChannelLayouts *ff_all_channel_layouts(void);
129	AVFilterFormats *ff_all_samplerates(void);
130
131	/**
132	* Construct an AVFilterChannelLayouts coding for any channel layout, with
133	* known or unknown disposition.
134	*/
135	AVFilterChannelLayouts *ff_all_channel_counts(void);
136
137	AVFilterChannelLayouts avfilter_make_format64_list(const int64_t fmts);
138
139
140	/**
141	* A helper for query_formats() which sets all links to the same list of channel
142	* layouts/sample rates. If there are no links hooked to this filter, the list
143	* is freed.
144	*/
145	void ff_set_common_channel_layouts(AVFilterContext *ctx,
146	AVFilterChannelLayouts *layouts);
147	void ff_set_common_samplerates(AVFilterContext *ctx,
148	AVFilterFormats *samplerates);
149
150	/**
151	* A helper for query_formats() which sets all links to the same list of
152	* formats. If there are no links hooked to this filter, the list of formats is
153	* freed.
154	*/
155	void ff_set_common_formats(AVFilterContext ctx, AVFilterFormats formats);
156
157	int ff_add_channel_layout(AVFilterChannelLayouts **l, uint64_t channel_layout);
158
159	/**
160	* Add *ref as a new reference to f.
161	*/
162	void ff_channel_layouts_ref(AVFilterChannelLayouts *f,
163	AVFilterChannelLayouts **ref);
164
165	/**
166	* Remove a reference to a channel layouts list.
167	*/
168	void ff_channel_layouts_unref(AVFilterChannelLayouts **ref);
169
170	void ff_channel_layouts_changeref(AVFilterChannelLayouts **oldref,
171	AVFilterChannelLayouts **newref);
172
173	int ff_default_query_formats(AVFilterContext *ctx);
174
175	/**
176	* Set the formats list to all existing formats.
177	* This function behaves like ff_default_query_formats(), except it also
178	* accepts channel layouts with unknown disposition. It should only be used
179	* with audio filters.
180	*/
181	int ff_query_formats_all(AVFilterContext *ctx);
182
183
184	/**
185	* Create a list of supported formats. This is intended for use in
186	* AVFilter->query_formats().
187	*
188	* @param fmts list of media formats, terminated by -1
189	* @return the format list, with no existing references
190	*/
191	AVFilterFormats ff_make_format_list(const int fmts);
192
193	/**
194	* Add fmt to the list of media formats contained in *avff.
195	* If *avff is NULL the function allocates the filter formats struct
196	* and puts its pointer in *avff.
197	*
198	* @return a non negative value in case of success, or a negative
199	* value corresponding to an AVERROR code in case of error
200	*/
201	int ff_add_format(AVFilterFormats **avff, int64_t fmt);
202
203	/**
204	* Return a list of all formats supported by FFmpeg for the given media type.
205	*/
206	AVFilterFormats *ff_all_formats(enum AVMediaType type);
207
208	/**
209	* Construct a formats list containing all planar sample formats.
210	*/
211	AVFilterFormats *ff_planar_sample_fmts(void);
212
213	/**
214	* Return a format list which contains the intersection of the formats of
215	* a and b. Also, all the references of a, all the references of b, and
216	* a and b themselves will be deallocated.
217	*
218	* If a and b do not share any common formats, neither is modified, and NULL
219	* is returned.
220	*/
221	AVFilterFormats ff_merge_formats(AVFilterFormats a, AVFilterFormats *b,
222	enum AVMediaType type);
223
224	/**
225	* Add *ref as a new reference to formats.
226	* That is the pointers will point like in the ascii art below:
227	* ________
228	* \|formats \|<--------.
229	* \| ____ \| ____\|___________________
230	* \| \|refs\| \| \| __\|_
231	* \| \|* * \| \| \| \| \| \| AVFilterLink
232	* \| \|* --------->\|ref\|
233	* \| \|____\| \| \| \|____\|
234	* \|________\| \|________________________
235	*/
236	void ff_formats_ref(AVFilterFormats formats, AVFilterFormats *ref);
237
238	/**
239	* If ref is non-NULL, remove ref as a reference to the format list
240	* it currently points to, deallocates that list if this was the last
241	* reference, and sets *ref to NULL.
242	*
243	* Before After
244	* ________ ________ NULL
245	* \|formats \|<--------. \|formats \| ^
246	* \| ____ \| ____\|________________ \| ____ \| ____\|________________
247	* \| \|refs\| \| \| __\|_ \| \|refs\| \| \| __\|_
248	* \| \|* * \| \| \| \| \| \| AVFilterLink \| \|* * \| \| \| \| \| \| AVFilterLink
249	* \| \|* --------->\|ref\| \| \|* \| \| \| \|*ref\|
250	* \| \|____\| \| \| \|____\| \| \|____\| \| \| \|____\|
251	* \|________\| \|_____________________ \|________\| \|_____________________
252	*/
253	void ff_formats_unref(AVFilterFormats **ref);
254
255	/**
256	*
257	* Before After
258	* ________ ________
259	* \|formats \|<---------. \|formats \|<---------.
260	* \| ____ \| ___\|___ \| ____ \| ___\|___
261	* \| \|refs\| \| \| \| \| \| \|refs\| \| \| \| \| NULL
262	* \| \|* --------->\|oldref\| \| \|* --------->\|newref\| ^
263	* \| \|* * \| \| \|_______\| \| \|* * \| \| \|_______\| ___\|___
264	* \| \|____\| \| \| \|____\| \| \| \| \|
265	* \|________\| \|________\| \|*oldref\|
266	* \|_______\|
267	*/
268	void ff_formats_changeref(AVFilterFormats oldref, AVFilterFormats newref);
269
270	#endif /* AVFILTER_FORMATS_H */