1 files changed, 126 insertions, 0 deletions
diff --git a/libavcodec/v4l2_m2m.h b/libavcodec/v4l2_m2m.h
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+++ b/libavcodec/v4l2_m2m.h
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+/*
+ * 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 cannot 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 cannot 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 */