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
38 static AVRational v4l2_timebase = { 1, USEC_PER_SEC };
40 static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
42 return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
43 container_of(buf->context, V4L2m2mContext, output) :
44 container_of(buf->context, V4L2m2mContext, capture);
47 static inline AVCodecContext *logger(V4L2Buffer *buf)
49 return buf_to_m2mctx(buf)->avctx;
52 static inline AVRational v4l2_get_timebase(V4L2Buffer *avbuf)
54 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
56 if (s->avctx->pkt_timebase.num)
57 return s->avctx->pkt_timebase;
58 return s->avctx->time_base;
61 static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
65 if (pts == AV_NOPTS_VALUE)
68 /* convert pts to v4l2 timebase */
69 v4l2_pts = av_rescale_q(pts, v4l2_get_timebase(out), v4l2_timebase);
70 out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
71 out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
74 static inline int64_t v4l2_get_pts(V4L2Buffer *avbuf)
78 /* convert pts back to encoder timebase */
79 v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
80 avbuf->buf.timestamp.tv_usec;
82 return av_rescale_q(v4l2_pts, v4l2_timebase, v4l2_get_timebase(avbuf));
85 static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
87 enum v4l2_ycbcr_encoding ycbcr;
88 enum v4l2_colorspace cs;
90 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
91 buf->context->format.fmt.pix_mp.colorspace :
92 buf->context->format.fmt.pix.colorspace;
94 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
95 buf->context->format.fmt.pix_mp.ycbcr_enc:
96 buf->context->format.fmt.pix.ycbcr_enc;
99 case V4L2_YCBCR_ENC_XV709:
100 case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
101 case V4L2_YCBCR_ENC_XV601:
102 case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
108 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
109 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
110 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
111 case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
116 return AVCOL_PRI_UNSPECIFIED;
119 static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
121 enum v4l2_quantization qt;
123 qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
124 buf->context->format.fmt.pix_mp.quantization :
125 buf->context->format.fmt.pix.quantization;
128 case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
129 case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
134 return AVCOL_RANGE_UNSPECIFIED;
137 static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
139 enum v4l2_ycbcr_encoding ycbcr;
140 enum v4l2_colorspace cs;
142 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
143 buf->context->format.fmt.pix_mp.colorspace :
144 buf->context->format.fmt.pix.colorspace;
146 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
147 buf->context->format.fmt.pix_mp.ycbcr_enc:
148 buf->context->format.fmt.pix.ycbcr_enc;
151 case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
152 case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
153 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
154 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
155 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
156 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
157 case V4L2_COLORSPACE_BT2020:
158 if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
159 return AVCOL_SPC_BT2020_CL;
161 return AVCOL_SPC_BT2020_NCL;
166 return AVCOL_SPC_UNSPECIFIED;
169 static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
171 enum v4l2_ycbcr_encoding ycbcr;
172 enum v4l2_xfer_func xfer;
173 enum v4l2_colorspace cs;
175 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
176 buf->context->format.fmt.pix_mp.colorspace :
177 buf->context->format.fmt.pix.colorspace;
179 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
180 buf->context->format.fmt.pix_mp.ycbcr_enc:
181 buf->context->format.fmt.pix.ycbcr_enc;
183 xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
184 buf->context->format.fmt.pix_mp.xfer_func:
185 buf->context->format.fmt.pix.xfer_func;
188 case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
189 case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
195 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
196 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
197 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
198 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
204 case V4L2_YCBCR_ENC_XV709:
205 case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
210 return AVCOL_TRC_UNSPECIFIED;
213 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
215 V4L2Buffer* avbuf = opaque;
216 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
218 if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
219 atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
222 if (!atomic_load(&s->refcount))
223 sem_post(&s->refsync);
226 /* no need to queue more buffers to the driver */
227 avbuf->status = V4L2BUF_AVAILABLE;
229 else if (avbuf->context->streamon)
230 ff_v4l2_buffer_enqueue(avbuf);
233 av_buffer_unref(&avbuf->context_ref);
237 static int v4l2_buf_increase_ref(V4L2Buffer *in)
239 V4L2m2mContext *s = buf_to_m2mctx(in);
242 atomic_fetch_add(&in->context_refcount, 1);
244 in->context_ref = av_buffer_ref(s->self_ref);
245 if (!in->context_ref)
246 return AVERROR(ENOMEM);
248 in->context_refcount = 1;
251 in->status = V4L2BUF_RET_USER;
252 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
257 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
261 if (plane >= in->num_planes)
262 return AVERROR(EINVAL);
264 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
265 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
266 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
268 return AVERROR(ENOMEM);
270 ret = v4l2_buf_increase_ref(in);
272 av_buffer_unref(buf);
277 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, int offset, AVBufferRef* bref)
279 unsigned int bytesused, length;
281 if (plane >= out->num_planes)
282 return AVERROR(EINVAL);
284 length = out->plane_info[plane].length;
285 bytesused = FFMIN(size+offset, length);
287 memcpy((uint8_t*)out->plane_info[plane].mm_addr+offset, data, FFMIN(size, length-offset));
289 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
290 out->planes[plane].bytesused = bytesused;
291 out->planes[plane].length = length;
293 out->buf.bytesused = bytesused;
294 out->buf.length = length;
300 static int v4l2_buffer_buf_to_swframe(AVFrame *frame, V4L2Buffer *avbuf)
304 frame->format = avbuf->context->av_pix_fmt;
306 for (i = 0; i < avbuf->num_planes; i++) {
307 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
311 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
312 frame->data[i] = frame->buf[i]->data;
315 /* fixup special cases */
316 switch (avbuf->context->av_pix_fmt) {
317 case AV_PIX_FMT_NV12:
318 case AV_PIX_FMT_NV21:
319 if (avbuf->num_planes > 1)
321 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
322 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
325 case AV_PIX_FMT_YUV420P:
326 if (avbuf->num_planes > 1)
328 frame->linesize[1] = avbuf->plane_info[0].bytesperline >> 1;
329 frame->linesize[2] = avbuf->plane_info[0].bytesperline >> 1;
330 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
331 frame->data[2] = frame->data[1] + ((avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height) >> 2);
341 static int v4l2_buffer_swframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
344 struct v4l2_format fmt = out->context->format;
345 int pixel_format = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
346 fmt.fmt.pix_mp.pixelformat : fmt.fmt.pix.pixelformat;
347 int height = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
348 fmt.fmt.pix_mp.height : fmt.fmt.pix.height;
349 int is_planar_format = 0;
351 switch (pixel_format) {
352 case V4L2_PIX_FMT_YUV420M:
353 case V4L2_PIX_FMT_YVU420M:
354 case V4L2_PIX_FMT_YUV422M:
355 case V4L2_PIX_FMT_YVU422M:
356 case V4L2_PIX_FMT_YUV444M:
357 case V4L2_PIX_FMT_YVU444M:
358 case V4L2_PIX_FMT_NV12M:
359 case V4L2_PIX_FMT_NV21M:
360 case V4L2_PIX_FMT_NV12MT_16X16:
361 case V4L2_PIX_FMT_NV12MT:
362 case V4L2_PIX_FMT_NV16M:
363 case V4L2_PIX_FMT_NV61M:
364 is_planar_format = 1;
367 if (!is_planar_format) {
368 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
372 for (i = 0; i < desc->nb_components; i++)
373 planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
375 for (i = 0; i < planes_nb; i++) {
376 int size, h = height;
377 if (i == 1 || i == 2) {
378 h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
380 size = frame->linesize[i] * h;
381 ret = v4l2_bufref_to_buf(out, 0, frame->data[i], size, offset, frame->buf[i]);
389 for (i = 0; i < out->num_planes; i++) {
390 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, 0, frame->buf[i]);
398 /******************************************************************************
400 * V4L2Buffer interface
402 ******************************************************************************/
404 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
406 v4l2_set_pts(out, frame->pts);
408 return v4l2_buffer_swframe_to_buf(frame, out);
411 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
415 av_frame_unref(frame);
417 /* 1. get references to the actual data */
418 ret = v4l2_buffer_buf_to_swframe(frame, avbuf);
422 /* 2. get frame information */
423 frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
424 frame->color_primaries = v4l2_get_color_primaries(avbuf);
425 frame->colorspace = v4l2_get_color_space(avbuf);
426 frame->color_range = v4l2_get_color_range(avbuf);
427 frame->color_trc = v4l2_get_color_trc(avbuf);
428 frame->pts = v4l2_get_pts(avbuf);
429 frame->pkt_dts = AV_NOPTS_VALUE;
431 /* these values are updated also during re-init in v4l2_process_driver_event */
432 frame->height = avbuf->context->height;
433 frame->width = avbuf->context->width;
434 frame->sample_aspect_ratio = avbuf->context->sample_aspect_ratio;
436 /* 3. report errors upstream */
437 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
438 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
439 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
445 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
449 av_packet_unref(pkt);
450 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
454 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
455 pkt->data = pkt->buf->data;
457 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
458 pkt->flags |= AV_PKT_FLAG_KEY;
460 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
461 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
462 pkt->flags |= AV_PKT_FLAG_CORRUPT;
465 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
470 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
474 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, 0, pkt->buf);
478 v4l2_set_pts(out, pkt->pts);
480 if (pkt->flags & AV_PKT_FLAG_KEY)
481 out->flags = V4L2_BUF_FLAG_KEYFRAME;
486 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
488 V4L2Context *ctx = avbuf->context;
491 avbuf->buf.memory = V4L2_MEMORY_MMAP;
492 avbuf->buf.type = ctx->type;
493 avbuf->buf.index = index;
495 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
496 avbuf->buf.length = VIDEO_MAX_PLANES;
497 avbuf->buf.m.planes = avbuf->planes;
500 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
502 return AVERROR(errno);
504 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
505 avbuf->num_planes = 0;
507 /* in MP, the V4L2 API states that buf.length means num_planes */
508 if (avbuf->num_planes >= avbuf->buf.length)
510 if (avbuf->buf.m.planes[avbuf->num_planes].length)
514 avbuf->num_planes = 1;
516 for (i = 0; i < avbuf->num_planes; i++) {
518 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
519 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
520 ctx->format.fmt.pix.bytesperline;
522 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
523 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
524 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
525 PROT_READ | PROT_WRITE, MAP_SHARED,
526 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
528 avbuf->plane_info[i].length = avbuf->buf.length;
529 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
530 PROT_READ | PROT_WRITE, MAP_SHARED,
531 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
534 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
535 return AVERROR(ENOMEM);
538 avbuf->status = V4L2BUF_AVAILABLE;
540 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
543 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
544 avbuf->buf.m.planes = avbuf->planes;
545 avbuf->buf.length = avbuf->num_planes;
548 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
549 avbuf->buf.length = avbuf->planes[0].length;
552 return ff_v4l2_buffer_enqueue(avbuf);
555 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
559 avbuf->buf.flags = avbuf->flags;
561 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
563 return AVERROR(errno);
565 avbuf->status = V4L2BUF_IN_DRIVER;