diff options
Diffstat (limited to 'libavcodec/v4l2_buffers.c')
| -rw-r--r-- | libavcodec/v4l2_buffers.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/libavcodec/v4l2_buffers.c b/libavcodec/v4l2_buffers.c new file mode 100644 index 0000000..aef911f --- /dev/null +++ b/libavcodec/v4l2_buffers.c @@ -0,0 +1,478 @@ +/* + * 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; +} |
