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/*
* V4L2 buffer 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
*/
#include <linux/videodev2.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <fcntl.h>
#include <poll.h>
#include "libavcodec/avcodec.h"
#include "libavcodec/internal.h"
#include "v4l2_context.h"
#include "v4l2_buffers.h"
#include "v4l2_m2m.h"
#define USEC_PER_SEC 1000000
static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
{
return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
container_of(buf->context, V4L2m2mContext, output) :
container_of(buf->context, V4L2m2mContext, capture);
}
static inline AVCodecContext *logger(V4L2Buffer *buf)
{
return buf_to_m2mctx(buf)->avctx;
}
static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
{
V4L2m2mContext *s = buf_to_m2mctx(out);
AVRational v4l2_timebase = { 1, USEC_PER_SEC };
int64_t v4l2_pts;
if (pts == AV_NOPTS_VALUE)
pts = 0;
/* convert pts to v4l2 timebase */
v4l2_pts = av_rescale_q(pts, s->avctx->time_base, v4l2_timebase);
out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
}
static inline uint64_t v4l2_get_pts(V4L2Buffer *avbuf)
{
V4L2m2mContext *s = buf_to_m2mctx(avbuf);
AVRational v4l2_timebase = { 1, USEC_PER_SEC };
int64_t v4l2_pts;
/* convert pts back to encoder timebase */
v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
avbuf->buf.timestamp.tv_usec;
return av_rescale_q(v4l2_pts, v4l2_timebase, s->avctx->time_base);
}
static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
{
enum v4l2_ycbcr_encoding ycbcr;
enum v4l2_colorspace cs;
cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.colorspace :
buf->context->format.fmt.pix.colorspace;
ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.ycbcr_enc:
buf->context->format.fmt.pix.ycbcr_enc;
switch(ycbcr) {
case V4L2_YCBCR_ENC_XV709:
case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
case V4L2_YCBCR_ENC_XV601:
case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
default:
break;
}
switch(cs) {
case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
default:
break;
}
return AVCOL_PRI_UNSPECIFIED;
}
static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
{
enum v4l2_quantization qt;
qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.quantization :
buf->context->format.fmt.pix.quantization;
switch (qt) {
case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
default:
break;
}
return AVCOL_RANGE_UNSPECIFIED;
}
static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
{
enum v4l2_ycbcr_encoding ycbcr;
enum v4l2_colorspace cs;
cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.colorspace :
buf->context->format.fmt.pix.colorspace;
ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.ycbcr_enc:
buf->context->format.fmt.pix.ycbcr_enc;
switch(cs) {
case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
case V4L2_COLORSPACE_BT2020:
if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
return AVCOL_SPC_BT2020_CL;
else
return AVCOL_SPC_BT2020_NCL;
default:
break;
}
return AVCOL_SPC_UNSPECIFIED;
}
static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
{
enum v4l2_ycbcr_encoding ycbcr;
enum v4l2_xfer_func xfer;
enum v4l2_colorspace cs;
cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.colorspace :
buf->context->format.fmt.pix.colorspace;
ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.ycbcr_enc:
buf->context->format.fmt.pix.ycbcr_enc;
xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
buf->context->format.fmt.pix_mp.xfer_func:
buf->context->format.fmt.pix.xfer_func;
switch (xfer) {
case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
default:
break;
}
switch (cs) {
case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
default:
break;
}
switch (ycbcr) {
case V4L2_YCBCR_ENC_XV709:
case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
default:
break;
}
return AVCOL_TRC_UNSPECIFIED;
}
static void v4l2_free_buffer(void *opaque, uint8_t *unused)
{
V4L2Buffer* avbuf = opaque;
V4L2m2mContext *s = buf_to_m2mctx(avbuf);
if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
if (s->reinit) {
if (!atomic_load(&s->refcount))
sem_post(&s->refsync);
} else {
if (s->draining) {
/* no need to queue more buffers to the driver */
avbuf->status = V4L2BUF_AVAILABLE;
}
else if (avbuf->context->streamon)
ff_v4l2_buffer_enqueue(avbuf);
}
av_buffer_unref(&avbuf->context_ref);
}
}
static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
{
V4L2m2mContext *s = buf_to_m2mctx(in);
if (plane >= in->num_planes)
return AVERROR(EINVAL);
/* even though most encoders return 0 in data_offset encoding vp8 does require this value */
*buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
in->plane_info[plane].length, v4l2_free_buffer, in, 0);
if (!*buf)
return AVERROR(ENOMEM);
if (in->context_ref)
atomic_fetch_add(&in->context_refcount, 1);
else {
in->context_ref = av_buffer_ref(s->self_ref);
if (!in->context_ref) {
av_buffer_unref(buf);
return AVERROR(ENOMEM);
}
in->context_refcount = 1;
}
in->status = V4L2BUF_RET_USER;
atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
return 0;
}
static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, AVBufferRef* bref)
{
unsigned int bytesused, length;
if (plane >= out->num_planes)
return AVERROR(EINVAL);
bytesused = FFMIN(size, out->plane_info[plane].length);
length = out->plane_info[plane].length;
memcpy(out->plane_info[plane].mm_addr, data, FFMIN(size, out->plane_info[plane].length));
if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
out->planes[plane].bytesused = bytesused;
out->planes[plane].length = length;
} else {
out->buf.bytesused = bytesused;
out->buf.length = length;
}
return 0;
}
/******************************************************************************
*
* V4L2uffer interface
*
******************************************************************************/
int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer* out)
{
int i, ret;
for(i = 0; i < out->num_planes; i++) {
ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, frame->buf[i]);
if (ret)
return ret;
}
v4l2_set_pts(out, frame->pts);
return 0;
}
int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
{
V4L2m2mContext *s = buf_to_m2mctx(avbuf);
int i, ret;
av_frame_unref(frame);
/* 1. get references to the actual data */
for (i = 0; i < avbuf->num_planes; i++) {
ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
if (ret)
return ret;
frame->linesize[i] = avbuf->plane_info[i].bytesperline;
frame->data[i] = frame->buf[i]->data;
}
/* 1.1 fixup special cases */
switch (avbuf->context->av_pix_fmt) {
case AV_PIX_FMT_NV12:
if (avbuf->num_planes > 1)
break;
frame->linesize[1] = avbuf->plane_info[0].bytesperline;
frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
break;
default:
break;
}
/* 2. get frame information */
frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
frame->format = avbuf->context->av_pix_fmt;
frame->color_primaries = v4l2_get_color_primaries(avbuf);
frame->colorspace = v4l2_get_color_space(avbuf);
frame->color_range = v4l2_get_color_range(avbuf);
frame->color_trc = v4l2_get_color_trc(avbuf);
frame->pts = v4l2_get_pts(avbuf);
/* these two values are updated also during re-init in v4l2_process_driver_event */
frame->height = s->output.height;
frame->width = s->output.width;
/* 3. report errors upstream */
if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
}
return 0;
}
int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
{
int ret;
av_packet_unref(pkt);
ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
if (ret)
return ret;
pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
pkt->data = pkt->buf->data;
if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
pkt->flags |= AV_PKT_FLAG_KEY;
if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
pkt->flags |= AV_PKT_FLAG_CORRUPT;
}
pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
return 0;
}
int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
{
int ret;
ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, pkt->buf);
if (ret)
return ret;
v4l2_set_pts(out, pkt->pts);
if (pkt->flags & AV_PKT_FLAG_KEY)
out->flags = V4L2_BUF_FLAG_KEYFRAME;
return 0;
}
int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
{
V4L2Context *ctx = avbuf->context;
int ret, i;
avbuf->buf.memory = V4L2_MEMORY_MMAP;
avbuf->buf.type = ctx->type;
avbuf->buf.index = index;
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
avbuf->buf.length = VIDEO_MAX_PLANES;
avbuf->buf.m.planes = avbuf->planes;
}
ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
if (ret < 0)
return AVERROR(errno);
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
avbuf->num_planes = 0;
for (;;) {
/* in MP, the V4L2 API states that buf.length means num_planes */
if (avbuf->num_planes >= avbuf->buf.length)
break;
if (avbuf->buf.m.planes[avbuf->num_planes].length)
avbuf->num_planes++;
}
} else
avbuf->num_planes = 1;
for (i = 0; i < avbuf->num_planes; i++) {
avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
ctx->format.fmt.pix.bytesperline;
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
PROT_READ | PROT_WRITE, MAP_SHARED,
buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
} else {
avbuf->plane_info[i].length = avbuf->buf.length;
avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
PROT_READ | PROT_WRITE, MAP_SHARED,
buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
}
if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
return AVERROR(ENOMEM);
}
avbuf->status = V4L2BUF_AVAILABLE;
if (V4L2_TYPE_IS_OUTPUT(ctx->type))
return 0;
if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
avbuf->buf.m.planes = avbuf->planes;
avbuf->buf.length = avbuf->num_planes;
} else {
avbuf->buf.bytesused = avbuf->planes[0].bytesused;
avbuf->buf.length = avbuf->planes[0].length;
}
return ff_v4l2_buffer_enqueue(avbuf);
}
int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
{
int ret;
avbuf->buf.flags = avbuf->flags;
ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
if (ret < 0)
return AVERROR(errno);
avbuf->status = V4L2BUF_IN_DRIVER;
return 0;
}