2 * V4L2 mem2mem helper functions
4 * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
5 * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #ifndef AVCODEC_V4L2_M2M_H
25 #define AVCODEC_V4L2_M2M_H
27 #include <semaphore.h>
30 #include <linux/videodev2.h>
32 #include "libavcodec/avcodec.h"
33 #include "v4l2_context.h"
35 #define container_of(ptr, type, member) ({ \
36 const __typeof__(((type *)0)->member ) *__mptr = (ptr); \
37 (type *)((char *)__mptr - offsetof(type,member) );})
39 #define V4L_M2M_DEFAULT_OPTS \
40 { "num_output_buffers", "Number of buffers in the output context",\
41 OFFSET(num_output_buffers), AV_OPT_TYPE_INT, { .i64 = 16 }, 6, INT_MAX, FLAGS }
43 typedef struct V4L2m2mContext {
44 char devname[PATH_MAX];
47 /* the codec context queues */
51 /* dynamic stream reconfig */
52 AVCodecContext *avctx;
57 /* null frame/packet received */
61 /* Reference to a frame. Only used during encoding */
64 /* Reference to self; only valid while codec is active. */
65 AVBufferRef *self_ref;
67 /* reference back to V4L2m2mPriv */
71 typedef struct V4L2m2mPriv {
74 V4L2m2mContext *context;
75 AVBufferRef *context_ref;
77 int num_output_buffers;
78 int num_capture_buffers;
82 * Allocate a new context and references for a V4L2 M2M instance.
84 * @param[in] ctx The V4L2m2mPriv instantiated by the encoder/decoder.
85 * @param[out] ctx The V4L2m2mContext.
87 * @returns 0 in success, a negative error code otherwise.
89 int ff_v4l2_m2m_create_context(V4L2m2mPriv *priv, V4L2m2mContext **s);
93 * Probes the video nodes looking for the required codec capabilities.
95 * @param[in] ctx The V4L2m2mPriv instantiated by the encoder/decoder.
97 * @returns 0 if a driver is found, a negative number otherwise.
99 int ff_v4l2_m2m_codec_init(V4L2m2mPriv *priv);
102 * Releases all the codec resources if all AVBufferRefs have been returned to the
103 * ctx. Otherwise keep the driver open.
105 * @param[in] The V4L2m2mPriv instantiated by the encoder/decoder.
110 int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv);
113 * Reinitializes the V4L2m2mContext when the driver cannot continue processing
114 * with the capture parameters.
116 * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder.
118 * @returns 0 in case of success, negative number otherwise
120 int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *ctx);
123 * Reinitializes the V4L2m2mContext when the driver cannot continue processing
124 * with the any of the current V4L2Contexts (ie, changes in output and capture).
126 * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder.
128 * @returns 0 in case of success, negative number otherwise
130 int ff_v4l2_m2m_codec_full_reinit(V4L2m2mContext *ctx);
132 #endif /* AVCODEC_V4L2_M2M_H */