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Diffstat (limited to 'libavcodec/v4l2_m2m.h')
-rw-r--r-- | libavcodec/v4l2_m2m.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/libavcodec/v4l2_m2m.h b/libavcodec/v4l2_m2m.h new file mode 100644 index 0000000..452bf0d --- /dev/null +++ b/libavcodec/v4l2_m2m.h @@ -0,0 +1,126 @@ +/* + * V4L2 mem2mem helper functions + * + * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org> + * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org> + * + * 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 AVCODEC_V4L2_M2M_H +#define AVCODEC_V4L2_M2M_H + +#include <semaphore.h> +#include <unistd.h> +#include <dirent.h> +#include <linux/videodev2.h> + +#include "libavcodec/avcodec.h" +#include "v4l2_context.h" + +#define container_of(ptr, type, member) ({ \ + const __typeof__(((type *)0)->member ) *__mptr = (ptr); \ + (type *)((char *)__mptr - offsetof(type,member) );}) + +#define V4L_M2M_DEFAULT_OPTS \ + { "num_output_buffers", "Number of buffers in the output context",\ + OFFSET(num_output_buffers), AV_OPT_TYPE_INT, { .i64 = 16 }, 6, INT_MAX, FLAGS } + +typedef struct V4L2m2mContext { + char devname[PATH_MAX]; + int fd; + + /* the codec context queues */ + V4L2Context capture; + V4L2Context output; + + /* dynamic stream reconfig */ + AVCodecContext *avctx; + sem_t refsync; + atomic_uint refcount; + int reinit; + + /* null frame/packet received */ + int draining; + + /* Reference to self; only valid while codec is active. */ + AVBufferRef *self_ref; +} V4L2m2mContext; + +typedef struct V4L2m2mPriv +{ + AVClass *class; + + V4L2m2mContext *context; + AVBufferRef *context_ref; + + int num_output_buffers; + int num_capture_buffers; +} V4L2m2mPriv; + +/** + * Allocate a new context and references for a V4L2 M2M instance. + * + * @param[in] ctx The AVCodecContext instantiated by the encoder/decoder. + * @param[out] ctx The V4L2m2mContext. + * + * @returns 0 in success, a negative error code otherwise. + */ +int ff_v4l2_m2m_create_context(AVCodecContext *avctx, V4L2m2mContext **s); + + +/** + * Probes the video nodes looking for the required codec capabilities. + * + * @param[in] ctx The AVCodecContext instantiated by the encoder/decoder. + * + * @returns 0 if a driver is found, a negative number otherwise. + */ +int ff_v4l2_m2m_codec_init(AVCodecContext *avctx); + +/** + * Releases all the codec resources if all AVBufferRefs have been returned to the + * ctx. Otherwise keep the driver open. + * + * @param[in] The AVCodecContext instantiated by the encoder/decoder. + * + * @returns 0 + * + */ +int ff_v4l2_m2m_codec_end(AVCodecContext *avctx); + +/** + * Reinitializes the V4L2m2mContext when the driver cant continue processing + * with the capture parameters. + * + * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder. + * + * @returns 0 in case of success, negative number otherwise + */ +int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *ctx); + +/** + * Reinitializes the V4L2m2mContext when the driver cant continue processing + * with the any of the current V4L2Contexts (ie, changes in output and capture). + * + * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder. + * + * @returns 0 in case of success, negative number otherwise + */ +int ff_v4l2_m2m_codec_full_reinit(V4L2m2mContext *ctx); + +#endif /* AVCODEC_V4L2_M2M_H */ |