FFmpeg/libavcodec/v4l2_m2m.c
Andriy Gelman 8bc7f69cef avcodec/v4l2_m2m_enc: buffer frame if it cannot be enqueued
Currently if the frame buffers are full, the frame is unrefed and
dropped.  Instead buffer the frame so that it is enqueued in the
next v4l2_receive_packet() call.  The behavior was observed on
DragonBoard 410c.

Signed-off-by: Andriy Gelman <andriy.gelman@gmail.com>
2020-08-23 13:42:07 -04:00

435 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_frame_unref(s->frame);
av_frame_free(&s->frame);
av_packet_unref(&s->buf_pkt);
av_free(s);
}
int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv)
{
V4L2m2mContext *s = priv->context;
int ret;
if (!s)
return 0;
if (s->fd >= 0) {
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;
priv->context->frame = av_frame_alloc();
if (!priv->context->frame) {
av_buffer_unref(&priv->context_ref);
*s = NULL; /* freed when unreferencing context_ref */
return AVERROR(ENOMEM);
}
return 0;
}