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24 #include <linux/videodev2.h>
25 #include <sys/ioctl.h>
42 if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT) &&
43 cap->capabilities & V4L2_CAP_STREAMING)
46 if (cap->capabilities & V4L2_CAP_VIDEO_M2M)
54 if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_OUTPUT_MPLANE) &&
55 cap->capabilities & V4L2_CAP_STREAMING)
58 if (cap->capabilities & V4L2_CAP_VIDEO_M2M_MPLANE)
66 struct v4l2_capability cap;
67 void *log_ctx =
s->avctx;
70 s->capture.done =
s->output.done = 0;
71 s->capture.name =
"capture";
72 s->output.name =
"output";
76 memset(&cap, 0,
sizeof(cap));
77 ret = ioctl(
s->fd, VIDIOC_QUERYCAP, &cap);
82 "driver '%s' on card '%s' in %s mode\n", cap.driver, cap.card,
87 s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
88 s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
93 s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
94 s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
103 void *log_ctx =
s->avctx;
106 s->fd = open(
s->devname, O_RDWR | O_NONBLOCK, 0);
127 if (close(
s->fd) < 0) {
139 void *log_ctx =
s->avctx;
141 struct v4l2_format ofmt, cfmt;
143 s->fd = open(
s->devname, O_RDWR | O_NONBLOCK, 0);
151 ofmt =
s->output.format;
152 cfmt =
s->capture.format;
155 ofmt.fmt.pix_mp.pixelformat :
156 ofmt.fmt.pix.pixelformat),
159 cfmt.fmt.pix_mp.pixelformat :
160 cfmt.fmt.pix.pixelformat),
193 if (close(
s->fd) < 0) {
210 void *log_ctx =
s->avctx;
226 while(
sem_wait(&
s->refsync) == -1 && errno == EINTR);
293 struct dirent *
entry;
298 dirp = opendir(
"/dev");
304 if (strncmp(
entry->d_name,
"video", 5))
318 memset(
s->devname, 0,
sizeof(
s->devname));
static void error(const char *err)
int ff_v4l2_context_init(V4L2Context *ctx)
Initializes a V4L2Context.
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
RefStruct is an API for creating reference-counted objects with minimal overhead.
int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *s)
Reinitializes the V4L2m2mContext when the driver cannot continue processing with the capture paramete...
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
static int v4l2_mplane_video(struct v4l2_capability *cap)
void ff_v4l2_context_release(V4L2Context *ctx)
Releases a V4L2Context.
static int v4l2_probe_driver(V4L2m2mContext *s)
V4L2m2mContext * context
RefStruct reference.
struct V4L2m2mContext * self_ref
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
int ff_v4l2_context_set_format(V4L2Context *ctx)
Sets the V4L2Context format in the v4l2 driver.
static int v4l2_splane_video(struct v4l2_capability *cap)
int ff_v4l2_context_get_format(V4L2Context *ctx, int probe)
Queries the driver for a valid v4l2 format and copies it to the context.
static void * av_refstruct_alloc_ext(size_t size, unsigned flags, void *opaque, void(*free_cb)(AVRefStructOpaque opaque, void *obj))
A wrapper around av_refstruct_alloc_ext_c() for the common case of a non-const qualified opaque.
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
int ff_v4l2_m2m_codec_init(V4L2m2mPriv *priv)
Probes the video nodes looking for the required codec capabilities.
#define atomic_load(object)
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your context
static void v4l2_m2m_destroy_context(AVRefStructOpaque unused, void *context)
static int v4l2_configure_contexts(V4L2m2mContext *s)
static int v4l2_prepare_contexts(V4L2m2mContext *s, int probe)
int ff_v4l2_m2m_create_context(V4L2m2mPriv *priv, V4L2m2mContext **s)
Allocate a new context and references for a V4L2 M2M instance.
int av_codec_is_decoder(const AVCodec *codec)
int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv)
Releases all the codec resources if all AVBufferRefs have been returned to the ctx.
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
#define AV_LOG_INFO
Standard information.
int ff_v4l2_context_set_status(V4L2Context *ctx, uint32_t cmd)
Sets the status of a V4L2Context.
void av_refstruct_unref(void *objp)
Decrement the reference count of the underlying object and automatically free the object if there are...
int num_buffers
Readonly after init.
#define sem_destroy(psem)
static int probe(const AVProbeData *p)
#define atomic_init(obj, value)
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
#define av_fourcc2str(fourcc)