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 "v4l2_context.h"
33 #include "v4l2_buffers.h"
36 #define USEC_PER_SEC 1000000
38 static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
40 return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
41 container_of(buf->context, V4L2m2mContext, output) :
42 container_of(buf->context, V4L2m2mContext, capture);
45 static inline AVCodecContext *logger(V4L2Buffer *buf)
47 return buf_to_m2mctx(buf)->avctx;
50 static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
52 V4L2m2mContext *s = buf_to_m2mctx(out);
53 AVRational v4l2_timebase = { 1, USEC_PER_SEC };
56 if (pts == AV_NOPTS_VALUE)
59 /* convert pts to v4l2 timebase */
60 v4l2_pts = av_rescale_q(pts, s->avctx->time_base, v4l2_timebase);
61 out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
62 out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
65 static inline uint64_t v4l2_get_pts(V4L2Buffer *avbuf)
67 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
68 AVRational v4l2_timebase = { 1, USEC_PER_SEC };
71 /* convert pts back to encoder timebase */
72 v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
73 avbuf->buf.timestamp.tv_usec;
75 return av_rescale_q(v4l2_pts, v4l2_timebase, s->avctx->time_base);
78 static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
80 enum v4l2_ycbcr_encoding ycbcr;
81 enum v4l2_colorspace cs;
83 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
84 buf->context->format.fmt.pix_mp.colorspace :
85 buf->context->format.fmt.pix.colorspace;
87 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
88 buf->context->format.fmt.pix_mp.ycbcr_enc:
89 buf->context->format.fmt.pix.ycbcr_enc;
92 case V4L2_YCBCR_ENC_XV709:
93 case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
94 case V4L2_YCBCR_ENC_XV601:
95 case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
101 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
102 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
103 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
104 case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
109 return AVCOL_PRI_UNSPECIFIED;
112 static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
114 enum v4l2_quantization qt;
116 qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
117 buf->context->format.fmt.pix_mp.quantization :
118 buf->context->format.fmt.pix.quantization;
121 case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
122 case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
127 return AVCOL_RANGE_UNSPECIFIED;
130 static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
132 enum v4l2_ycbcr_encoding ycbcr;
133 enum v4l2_colorspace cs;
135 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
136 buf->context->format.fmt.pix_mp.colorspace :
137 buf->context->format.fmt.pix.colorspace;
139 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
140 buf->context->format.fmt.pix_mp.ycbcr_enc:
141 buf->context->format.fmt.pix.ycbcr_enc;
144 case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
145 case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
146 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
147 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
148 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
149 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
150 case V4L2_COLORSPACE_BT2020:
151 if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
152 return AVCOL_SPC_BT2020_CL;
154 return AVCOL_SPC_BT2020_NCL;
159 return AVCOL_SPC_UNSPECIFIED;
162 static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
164 enum v4l2_ycbcr_encoding ycbcr;
165 enum v4l2_xfer_func xfer;
166 enum v4l2_colorspace cs;
168 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
169 buf->context->format.fmt.pix_mp.colorspace :
170 buf->context->format.fmt.pix.colorspace;
172 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
173 buf->context->format.fmt.pix_mp.ycbcr_enc:
174 buf->context->format.fmt.pix.ycbcr_enc;
176 xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
177 buf->context->format.fmt.pix_mp.xfer_func:
178 buf->context->format.fmt.pix.xfer_func;
181 case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
182 case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
188 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
189 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
190 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
191 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
197 case V4L2_YCBCR_ENC_XV709:
198 case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
203 return AVCOL_TRC_UNSPECIFIED;
206 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
208 V4L2Buffer* avbuf = opaque;
209 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
211 if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
212 atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
215 if (!atomic_load(&s->refcount))
216 sem_post(&s->refsync);
219 /* no need to queue more buffers to the driver */
220 avbuf->status = V4L2BUF_AVAILABLE;
222 else if (avbuf->context->streamon)
223 ff_v4l2_buffer_enqueue(avbuf);
226 av_buffer_unref(&avbuf->context_ref);
230 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
232 V4L2m2mContext *s = buf_to_m2mctx(in);
234 if (plane >= in->num_planes)
235 return AVERROR(EINVAL);
237 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
238 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
239 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
241 return AVERROR(ENOMEM);
244 atomic_fetch_add(&in->context_refcount, 1);
246 in->context_ref = av_buffer_ref(s->self_ref);
247 if (!in->context_ref) {
248 av_buffer_unref(buf);
249 return AVERROR(ENOMEM);
251 in->context_refcount = 1;
254 in->status = V4L2BUF_RET_USER;
255 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
260 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, AVBufferRef* bref)
262 unsigned int bytesused, length;
264 if (plane >= out->num_planes)
265 return AVERROR(EINVAL);
267 bytesused = FFMIN(size, out->plane_info[plane].length);
268 length = out->plane_info[plane].length;
270 memcpy(out->plane_info[plane].mm_addr, data, FFMIN(size, out->plane_info[plane].length));
272 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
273 out->planes[plane].bytesused = bytesused;
274 out->planes[plane].length = length;
276 out->buf.bytesused = bytesused;
277 out->buf.length = length;
283 /******************************************************************************
285 * V4L2uffer interface
287 ******************************************************************************/
289 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer* out)
293 for(i = 0; i < out->num_planes; i++) {
294 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, frame->buf[i]);
299 v4l2_set_pts(out, frame->pts);
304 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
306 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
309 av_frame_unref(frame);
311 /* 1. get references to the actual data */
312 for (i = 0; i < avbuf->num_planes; i++) {
313 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
317 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
318 frame->data[i] = frame->buf[i]->data;
321 /* 1.1 fixup special cases */
322 switch (avbuf->context->av_pix_fmt) {
323 case AV_PIX_FMT_NV12:
324 if (avbuf->num_planes > 1)
326 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
327 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
333 /* 2. get frame information */
334 frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
335 frame->format = avbuf->context->av_pix_fmt;
336 frame->color_primaries = v4l2_get_color_primaries(avbuf);
337 frame->colorspace = v4l2_get_color_space(avbuf);
338 frame->color_range = v4l2_get_color_range(avbuf);
339 frame->color_trc = v4l2_get_color_trc(avbuf);
340 frame->pts = v4l2_get_pts(avbuf);
342 /* these two values are updated also during re-init in v4l2_process_driver_event */
343 frame->height = s->output.height;
344 frame->width = s->output.width;
346 /* 3. report errors upstream */
347 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
348 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
349 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
355 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
359 av_packet_unref(pkt);
360 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
364 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
365 pkt->data = pkt->buf->data;
367 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
368 pkt->flags |= AV_PKT_FLAG_KEY;
370 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
371 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
372 pkt->flags |= AV_PKT_FLAG_CORRUPT;
375 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
380 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
384 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, pkt->buf);
388 v4l2_set_pts(out, pkt->pts);
390 if (pkt->flags & AV_PKT_FLAG_KEY)
391 out->flags = V4L2_BUF_FLAG_KEYFRAME;
396 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
398 V4L2Context *ctx = avbuf->context;
401 avbuf->buf.memory = V4L2_MEMORY_MMAP;
402 avbuf->buf.type = ctx->type;
403 avbuf->buf.index = index;
405 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
406 avbuf->buf.length = VIDEO_MAX_PLANES;
407 avbuf->buf.m.planes = avbuf->planes;
410 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
412 return AVERROR(errno);
414 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
415 avbuf->num_planes = 0;
417 /* in MP, the V4L2 API states that buf.length means num_planes */
418 if (avbuf->num_planes >= avbuf->buf.length)
420 if (avbuf->buf.m.planes[avbuf->num_planes].length)
424 avbuf->num_planes = 1;
426 for (i = 0; i < avbuf->num_planes; i++) {
428 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
429 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
430 ctx->format.fmt.pix.bytesperline;
432 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
433 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
434 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
435 PROT_READ | PROT_WRITE, MAP_SHARED,
436 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
438 avbuf->plane_info[i].length = avbuf->buf.length;
439 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
440 PROT_READ | PROT_WRITE, MAP_SHARED,
441 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
444 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
445 return AVERROR(ENOMEM);
448 avbuf->status = V4L2BUF_AVAILABLE;
450 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
453 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
454 avbuf->buf.m.planes = avbuf->planes;
455 avbuf->buf.length = avbuf->num_planes;
458 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
459 avbuf->buf.length = avbuf->planes[0].length;
462 return ff_v4l2_buffer_enqueue(avbuf);
465 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
469 avbuf->buf.flags = avbuf->flags;
471 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
473 return AVERROR(errno);
475 avbuf->status = V4L2BUF_IN_DRIVER;