ffmpeg/libavcodec/v4l2_m2m.c

420 lines
12 KiB
C

/*
* V4L mem2mem
*
* 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
*/
#include <linux/videodev2.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include "libavcodec/avcodec.h"
#include "libavcodec/internal.h"
#include "libavutil/pixdesc.h"
#include "libavutil/imgutils.h"
#include "libavutil/pixfmt.h"
#include "v4l2_context.h"
#include "v4l2_fmt.h"
#include "v4l2_m2m.h"
static inline int v4l2_splane_video(struct v4l2_capability *cap)
{
if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT) &&
cap->capabilities & V4L2_CAP_STREAMING)
return 1;
if (cap->capabilities & V4L2_CAP_VIDEO_M2M)
return 1;
return 0;
}
static inline int v4l2_mplane_video(struct v4l2_capability *cap)
{
if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_OUTPUT_MPLANE) &&
cap->capabilities & V4L2_CAP_STREAMING)
return 1;
if (cap->capabilities & V4L2_CAP_VIDEO_M2M_MPLANE)
return 1;
return 0;
}
static int v4l2_prepare_contexts(V4L2m2mContext *s, int probe)
{
struct v4l2_capability cap;
void *log_ctx = s->avctx;
int ret;
s->capture.done = s->output.done = 0;
s->capture.name = "capture";
s->output.name = "output";
atomic_init(&s->refcount, 0);
sem_init(&s->refsync, 0, 0);
memset(&cap, 0, sizeof(cap));
ret = ioctl(s->fd, VIDIOC_QUERYCAP, &cap);
if (ret < 0)
return ret;
av_log(log_ctx, probe ? AV_LOG_DEBUG : AV_LOG_INFO,
"driver '%s' on card '%s' in %s mode\n", cap.driver, cap.card,
v4l2_mplane_video(&cap) ? "mplane" :
v4l2_splane_video(&cap) ? "splane" : "unknown");
if (v4l2_mplane_video(&cap)) {
s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
return 0;
}
if (v4l2_splane_video(&cap)) {
s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
return 0;
}
return AVERROR(EINVAL);
}
static int v4l2_probe_driver(V4L2m2mContext *s)
{
void *log_ctx = s->avctx;
int ret;
s->fd = open(s->devname, O_RDWR | O_NONBLOCK, 0);
if (s->fd < 0)
return AVERROR(errno);
ret = v4l2_prepare_contexts(s, 1);
if (ret < 0)
goto done;
ret = ff_v4l2_context_get_format(&s->output, 1);
if (ret) {
av_log(log_ctx, AV_LOG_DEBUG, "v4l2 output format not supported\n");
goto done;
}
ret = ff_v4l2_context_get_format(&s->capture, 1);
if (ret) {
av_log(log_ctx, AV_LOG_DEBUG, "v4l2 capture format not supported\n");
goto done;
}
done:
if (close(s->fd) < 0) {
ret = AVERROR(errno);
av_log(log_ctx, AV_LOG_ERROR, "failure closing %s (%s)\n", s->devname, av_err2str(AVERROR(errno)));
}
s->fd = -1;
return ret;
}
static int v4l2_configure_contexts(V4L2m2mContext *s)
{
void *log_ctx = s->avctx;
int ret;
struct v4l2_format ofmt, cfmt;
s->fd = open(s->devname, O_RDWR | O_NONBLOCK, 0);
if (s->fd < 0)
return AVERROR(errno);
ret = v4l2_prepare_contexts(s, 0);
if (ret < 0)
goto error;
ofmt = s->output.format;
cfmt = s->capture.format;
av_log(log_ctx, AV_LOG_INFO, "requesting formats: output=%s capture=%s\n",
av_fourcc2str(V4L2_TYPE_IS_MULTIPLANAR(ofmt.type) ?
ofmt.fmt.pix_mp.pixelformat :
ofmt.fmt.pix.pixelformat),
av_fourcc2str(V4L2_TYPE_IS_MULTIPLANAR(cfmt.type) ?
cfmt.fmt.pix_mp.pixelformat :
cfmt.fmt.pix.pixelformat));
ret = ff_v4l2_context_set_format(&s->output);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "can't set v4l2 output format\n");
goto error;
}
ret = ff_v4l2_context_set_format(&s->capture);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "can't to set v4l2 capture format\n");
goto error;
}
ret = ff_v4l2_context_init(&s->output);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "no v4l2 output context's buffers\n");
goto error;
}
/* decoder's buffers need to be updated at a later stage */
if (s->avctx && !av_codec_is_decoder(s->avctx->codec)) {
ret = ff_v4l2_context_init(&s->capture);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "no v4l2 capture context's buffers\n");
goto error;
}
}
return 0;
error:
if (close(s->fd) < 0) {
ret = AVERROR(errno);
av_log(log_ctx, AV_LOG_ERROR, "error closing %s (%s)\n",
s->devname, av_err2str(AVERROR(errno)));
}
s->fd = -1;
return ret;
}
/******************************************************************************
*
* V4L2 M2M Interface
*
******************************************************************************/
int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *s)
{
void *log_ctx = s->avctx;
int ret;
av_log(log_ctx, AV_LOG_DEBUG, "reinit context\n");
/* 1. streamoff */
ret = ff_v4l2_context_set_status(&s->capture, VIDIOC_STREAMOFF);
if (ret)
av_log(log_ctx, AV_LOG_ERROR, "capture VIDIOC_STREAMOFF\n");
/* 2. unmap the capture buffers (v4l2 and ffmpeg):
* we must wait for all references to be released before being allowed
* to queue new buffers.
*/
av_log(log_ctx, AV_LOG_DEBUG, "waiting for user to release AVBufferRefs\n");
if (atomic_load(&s->refcount))
while(sem_wait(&s->refsync) == -1 && errno == EINTR);
ff_v4l2_context_release(&s->capture);
/* 3. get the new capture format */
ret = ff_v4l2_context_get_format(&s->capture, 0);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "query the new capture format\n");
return ret;
}
/* 4. set the capture format */
ret = ff_v4l2_context_set_format(&s->capture);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "setting capture format\n");
return ret;
}
/* 5. complete reinit */
s->draining = 0;
s->reinit = 0;
return 0;
}
int ff_v4l2_m2m_codec_full_reinit(V4L2m2mContext *s)
{
void *log_ctx = s->avctx;
int ret;
av_log(log_ctx, AV_LOG_DEBUG, "%s full reinit\n", s->devname);
/* wait for pending buffer references */
if (atomic_load(&s->refcount))
while(sem_wait(&s->refsync) == -1 && errno == EINTR);
ret = ff_v4l2_context_set_status(&s->output, VIDIOC_STREAMOFF);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "output VIDIOC_STREAMOFF\n");
goto error;
}
ret = ff_v4l2_context_set_status(&s->capture, VIDIOC_STREAMOFF);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "capture VIDIOC_STREAMOFF\n");
goto error;
}
/* release and unmmap the buffers */
ff_v4l2_context_release(&s->output);
ff_v4l2_context_release(&s->capture);
/* start again now that we know the stream dimensions */
s->draining = 0;
s->reinit = 0;
ret = ff_v4l2_context_get_format(&s->output, 0);
if (ret) {
av_log(log_ctx, AV_LOG_DEBUG, "v4l2 output format not supported\n");
goto error;
}
ret = ff_v4l2_context_get_format(&s->capture, 0);
if (ret) {
av_log(log_ctx, AV_LOG_DEBUG, "v4l2 capture format not supported\n");
goto error;
}
ret = ff_v4l2_context_set_format(&s->output);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "can't set v4l2 output format\n");
goto error;
}
ret = ff_v4l2_context_set_format(&s->capture);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "can't to set v4l2 capture format\n");
goto error;
}
ret = ff_v4l2_context_init(&s->output);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "no v4l2 output context's buffers\n");
goto error;
}
/* decoder's buffers need to be updated at a later stage */
if (s->avctx && !av_codec_is_decoder(s->avctx->codec)) {
ret = ff_v4l2_context_init(&s->capture);
if (ret) {
av_log(log_ctx, AV_LOG_ERROR, "no v4l2 capture context's buffers\n");
goto error;
}
}
return 0;
error:
return ret;
}
static void v4l2_m2m_destroy_context(void *opaque, uint8_t *context)
{
V4L2m2mContext *s = (V4L2m2mContext*)context;
ff_v4l2_context_release(&s->capture);
sem_destroy(&s->refsync);
close(s->fd);
av_free(s);
}
int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv)
{
V4L2m2mContext *s = priv->context;
int ret;
ret = ff_v4l2_context_set_status(&s->output, VIDIOC_STREAMOFF);
if (ret)
av_log(s->avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF %s\n", s->output.name);
ret = ff_v4l2_context_set_status(&s->capture, VIDIOC_STREAMOFF);
if (ret)
av_log(s->avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF %s\n", s->capture.name);
ff_v4l2_context_release(&s->output);
s->self_ref = NULL;
av_buffer_unref(&priv->context_ref);
return 0;
}
int ff_v4l2_m2m_codec_init(V4L2m2mPriv *priv)
{
int ret = AVERROR(EINVAL);
struct dirent *entry;
DIR *dirp;
V4L2m2mContext *s = priv->context;
dirp = opendir("/dev");
if (!dirp)
return AVERROR(errno);
for (entry = readdir(dirp); entry; entry = readdir(dirp)) {
if (strncmp(entry->d_name, "video", 5))
continue;
snprintf(s->devname, sizeof(s->devname), "/dev/%s", entry->d_name);
av_log(s->avctx, AV_LOG_DEBUG, "probing device %s\n", s->devname);
ret = v4l2_probe_driver(s);
if (!ret)
break;
}
closedir(dirp);
if (ret) {
av_log(s->avctx, AV_LOG_ERROR, "Could not find a valid device\n");
memset(s->devname, 0, sizeof(s->devname));
return ret;
}
av_log(s->avctx, AV_LOG_INFO, "Using device %s\n", s->devname);
return v4l2_configure_contexts(s);
}
int ff_v4l2_m2m_create_context(V4L2m2mPriv *priv, V4L2m2mContext **s)
{
*s = av_mallocz(sizeof(V4L2m2mContext));
if (!*s)
return AVERROR(ENOMEM);
priv->context_ref = av_buffer_create((uint8_t *) *s, sizeof(V4L2m2mContext),
&v4l2_m2m_destroy_context, NULL, 0);
if (!priv->context_ref) {
av_freep(s);
return AVERROR(ENOMEM);
}
/* assign the context */
priv->context = *s;
(*s)->priv = priv;
/* populate it */
priv->context->capture.num_buffers = priv->num_capture_buffers;
priv->context->output.num_buffers = priv->num_output_buffers;
priv->context->self_ref = priv->context_ref;
priv->context->fd = -1;
return 0;
}