2 * V4L2 buffer helper functions.
4 * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
5 * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #include <linux/videodev2.h>
25 #include <sys/ioctl.h>
30 #include "libavcodec/avcodec.h"
31 #include "libavcodec/internal.h"
32 #include "libavutil/pixdesc.h"
33 #include "v4l2_context.h"
34 #include "v4l2_buffers.h"
37 #define USEC_PER_SEC 1000000
39 static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
41 return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
42 container_of(buf->context, V4L2m2mContext, output) :
43 container_of(buf->context, V4L2m2mContext, capture);
46 static inline AVCodecContext *logger(V4L2Buffer *buf)
48 return buf_to_m2mctx(buf)->avctx;
51 static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
53 V4L2m2mContext *s = buf_to_m2mctx(out);
54 AVRational v4l2_timebase = { 1, USEC_PER_SEC };
57 if (pts == AV_NOPTS_VALUE)
60 /* convert pts to v4l2 timebase */
61 v4l2_pts = av_rescale_q(pts, s->avctx->time_base, v4l2_timebase);
62 out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
63 out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
66 static inline int64_t v4l2_get_pts(V4L2Buffer *avbuf)
68 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
69 AVRational v4l2_timebase = { 1, USEC_PER_SEC };
72 /* convert pts back to encoder timebase */
73 v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
74 avbuf->buf.timestamp.tv_usec;
76 return av_rescale_q(v4l2_pts, v4l2_timebase, s->avctx->time_base);
79 static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
81 enum v4l2_ycbcr_encoding ycbcr;
82 enum v4l2_colorspace cs;
84 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
85 buf->context->format.fmt.pix_mp.colorspace :
86 buf->context->format.fmt.pix.colorspace;
88 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
89 buf->context->format.fmt.pix_mp.ycbcr_enc:
90 buf->context->format.fmt.pix.ycbcr_enc;
93 case V4L2_YCBCR_ENC_XV709:
94 case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
95 case V4L2_YCBCR_ENC_XV601:
96 case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
102 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
103 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
104 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
105 case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
110 return AVCOL_PRI_UNSPECIFIED;
113 static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
115 enum v4l2_quantization qt;
117 qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
118 buf->context->format.fmt.pix_mp.quantization :
119 buf->context->format.fmt.pix.quantization;
122 case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
123 case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
128 return AVCOL_RANGE_UNSPECIFIED;
131 static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
133 enum v4l2_ycbcr_encoding ycbcr;
134 enum v4l2_colorspace cs;
136 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
137 buf->context->format.fmt.pix_mp.colorspace :
138 buf->context->format.fmt.pix.colorspace;
140 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
141 buf->context->format.fmt.pix_mp.ycbcr_enc:
142 buf->context->format.fmt.pix.ycbcr_enc;
145 case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
146 case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
147 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
148 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
149 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
150 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
151 case V4L2_COLORSPACE_BT2020:
152 if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
153 return AVCOL_SPC_BT2020_CL;
155 return AVCOL_SPC_BT2020_NCL;
160 return AVCOL_SPC_UNSPECIFIED;
163 static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
165 enum v4l2_ycbcr_encoding ycbcr;
166 enum v4l2_xfer_func xfer;
167 enum v4l2_colorspace cs;
169 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
170 buf->context->format.fmt.pix_mp.colorspace :
171 buf->context->format.fmt.pix.colorspace;
173 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
174 buf->context->format.fmt.pix_mp.ycbcr_enc:
175 buf->context->format.fmt.pix.ycbcr_enc;
177 xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
178 buf->context->format.fmt.pix_mp.xfer_func:
179 buf->context->format.fmt.pix.xfer_func;
182 case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
183 case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
189 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
190 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
191 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
192 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
198 case V4L2_YCBCR_ENC_XV709:
199 case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
204 return AVCOL_TRC_UNSPECIFIED;
207 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
209 V4L2Buffer* avbuf = opaque;
210 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
212 if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
213 atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
216 if (!atomic_load(&s->refcount))
217 sem_post(&s->refsync);
220 /* no need to queue more buffers to the driver */
221 avbuf->status = V4L2BUF_AVAILABLE;
223 else if (avbuf->context->streamon)
224 ff_v4l2_buffer_enqueue(avbuf);
227 av_buffer_unref(&avbuf->context_ref);
231 static int v4l2_buf_increase_ref(V4L2Buffer *in)
233 V4L2m2mContext *s = buf_to_m2mctx(in);
236 atomic_fetch_add(&in->context_refcount, 1);
238 in->context_ref = av_buffer_ref(s->self_ref);
239 if (!in->context_ref)
240 return AVERROR(ENOMEM);
242 in->context_refcount = 1;
245 in->status = V4L2BUF_RET_USER;
246 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
251 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
255 if (plane >= in->num_planes)
256 return AVERROR(EINVAL);
258 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
259 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
260 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
262 return AVERROR(ENOMEM);
264 ret = v4l2_buf_increase_ref(in);
266 av_buffer_unref(buf);
271 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, int offset, AVBufferRef* bref)
273 unsigned int bytesused, length;
275 if (plane >= out->num_planes)
276 return AVERROR(EINVAL);
278 length = out->plane_info[plane].length;
279 bytesused = FFMIN(size+offset, length);
281 memcpy((uint8_t*)out->plane_info[plane].mm_addr+offset, data, FFMIN(size, length-offset));
283 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
284 out->planes[plane].bytesused = bytesused;
285 out->planes[plane].length = length;
287 out->buf.bytesused = bytesused;
288 out->buf.length = length;
294 static int v4l2_buffer_buf_to_swframe(AVFrame *frame, V4L2Buffer *avbuf)
298 frame->format = avbuf->context->av_pix_fmt;
300 for (i = 0; i < avbuf->num_planes; i++) {
301 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
305 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
306 frame->data[i] = frame->buf[i]->data;
309 /* fixup special cases */
310 switch (avbuf->context->av_pix_fmt) {
311 case AV_PIX_FMT_NV12:
312 case AV_PIX_FMT_NV21:
313 if (avbuf->num_planes > 1)
315 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
316 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
319 case AV_PIX_FMT_YUV420P:
320 if (avbuf->num_planes > 1)
322 frame->linesize[1] = avbuf->plane_info[0].bytesperline >> 1;
323 frame->linesize[2] = avbuf->plane_info[0].bytesperline >> 1;
324 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
325 frame->data[2] = frame->data[1] + ((avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height) >> 2);
335 static int v4l2_buffer_swframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
338 struct v4l2_format fmt = out->context->format;
339 int pixel_format = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
340 fmt.fmt.pix_mp.pixelformat : fmt.fmt.pix.pixelformat;
341 int height = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
342 fmt.fmt.pix_mp.height : fmt.fmt.pix.height;
343 int is_planar_format = 0;
345 switch (pixel_format) {
346 case V4L2_PIX_FMT_YUV420M:
347 case V4L2_PIX_FMT_YVU420M:
348 case V4L2_PIX_FMT_YUV422M:
349 case V4L2_PIX_FMT_YVU422M:
350 case V4L2_PIX_FMT_YUV444M:
351 case V4L2_PIX_FMT_YVU444M:
352 case V4L2_PIX_FMT_NV12M:
353 case V4L2_PIX_FMT_NV21M:
354 case V4L2_PIX_FMT_NV12MT_16X16:
355 case V4L2_PIX_FMT_NV12MT:
356 case V4L2_PIX_FMT_NV16M:
357 case V4L2_PIX_FMT_NV61M:
358 is_planar_format = 1;
361 if (!is_planar_format) {
362 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
366 for (i = 0; i < desc->nb_components; i++)
367 planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
369 for (i = 0; i < planes_nb; i++) {
370 int size, h = height;
371 if (i == 1 || i == 2) {
372 h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
374 size = frame->linesize[i] * h;
375 ret = v4l2_bufref_to_buf(out, 0, frame->data[i], size, offset, frame->buf[i]);
383 for (i = 0; i < out->num_planes; i++) {
384 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, 0, frame->buf[i]);
392 /******************************************************************************
394 * V4L2Buffer interface
396 ******************************************************************************/
398 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
400 v4l2_set_pts(out, frame->pts);
402 return v4l2_buffer_swframe_to_buf(frame, out);
405 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
409 av_frame_unref(frame);
411 /* 1. get references to the actual data */
412 ret = v4l2_buffer_buf_to_swframe(frame, avbuf);
416 /* 2. get frame information */
417 frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
418 frame->color_primaries = v4l2_get_color_primaries(avbuf);
419 frame->colorspace = v4l2_get_color_space(avbuf);
420 frame->color_range = v4l2_get_color_range(avbuf);
421 frame->color_trc = v4l2_get_color_trc(avbuf);
422 frame->pts = v4l2_get_pts(avbuf);
424 /* these two values are updated also during re-init in v4l2_process_driver_event */
425 frame->height = avbuf->context->height;
426 frame->width = avbuf->context->width;
428 /* 3. report errors upstream */
429 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
430 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
431 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
437 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
441 av_packet_unref(pkt);
442 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
446 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
447 pkt->data = pkt->buf->data;
449 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
450 pkt->flags |= AV_PKT_FLAG_KEY;
452 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
453 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
454 pkt->flags |= AV_PKT_FLAG_CORRUPT;
457 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
462 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
466 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, 0, pkt->buf);
470 v4l2_set_pts(out, pkt->pts);
472 if (pkt->flags & AV_PKT_FLAG_KEY)
473 out->flags = V4L2_BUF_FLAG_KEYFRAME;
478 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
480 V4L2Context *ctx = avbuf->context;
483 avbuf->buf.memory = V4L2_MEMORY_MMAP;
484 avbuf->buf.type = ctx->type;
485 avbuf->buf.index = index;
487 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
488 avbuf->buf.length = VIDEO_MAX_PLANES;
489 avbuf->buf.m.planes = avbuf->planes;
492 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
494 return AVERROR(errno);
496 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
497 avbuf->num_planes = 0;
499 /* in MP, the V4L2 API states that buf.length means num_planes */
500 if (avbuf->num_planes >= avbuf->buf.length)
502 if (avbuf->buf.m.planes[avbuf->num_planes].length)
506 avbuf->num_planes = 1;
508 for (i = 0; i < avbuf->num_planes; i++) {
510 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
511 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
512 ctx->format.fmt.pix.bytesperline;
514 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
515 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
516 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
517 PROT_READ | PROT_WRITE, MAP_SHARED,
518 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
520 avbuf->plane_info[i].length = avbuf->buf.length;
521 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
522 PROT_READ | PROT_WRITE, MAP_SHARED,
523 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
526 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
527 return AVERROR(ENOMEM);
530 avbuf->status = V4L2BUF_AVAILABLE;
532 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
535 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
536 avbuf->buf.m.planes = avbuf->planes;
537 avbuf->buf.length = avbuf->num_planes;
540 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
541 avbuf->buf.length = avbuf->planes[0].length;
544 return ff_v4l2_buffer_enqueue(avbuf);
547 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
551 avbuf->buf.flags = avbuf->flags;
553 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
555 return AVERROR(errno);
557 avbuf->status = V4L2BUF_IN_DRIVER;