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authorTomasz Stanislawski <t.stanislaws@samsung.com>2012-10-04 10:18:27 (GMT)
committerSylwester Nawrocki <s.nawrocki@samsung.com>2012-10-04 11:22:13 (GMT)
commit15d10f8366cefb07d4c9d23e97752a4aba5763de (patch)
tree4889aebae3df6ea0f5014888021ce8036f8f282b /v4l2-hdmi-example
parent8b8182da6e16dfd0820ef2418c1bb66d4bcc8079 (diff)
v4l2-hdmi-example: version 0.1
Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Diffstat (limited to 'v4l2-hdmi-example')
-rw-r--r--v4l2-hdmi-example/CHANGELOG1
-rw-r--r--v4l2-hdmi-example/README12
-rw-r--r--v4l2-hdmi-example/main.c259
3 files changed, 272 insertions, 0 deletions
diff --git a/v4l2-hdmi-example/CHANGELOG b/v4l2-hdmi-example/CHANGELOG
new file mode 100644
index 0000000..673729c
--- /dev/null
+++ b/v4l2-hdmi-example/CHANGELOG
@@ -0,0 +1 @@
+Version 0.1
diff --git a/v4l2-hdmi-example/README b/v4l2-hdmi-example/README
new file mode 100644
index 0000000..52e67ad
--- /dev/null
+++ b/v4l2-hdmi-example/README
@@ -0,0 +1,12 @@
+
+Compilation:
+
+arm-linux-gnueabi-gcc main.c -o tvdemo -Ikernel/usr/include/ -std=gnu99 -lm -O2
+
+Command line example
+
+./tvdemo /dev/video10 720 480 0 0
+
+TODO:
+
+Add Makefile
diff --git a/v4l2-hdmi-example/main.c b/v4l2-hdmi-example/main.c
new file mode 100644
index 0000000..32308a1
--- /dev/null
+++ b/v4l2-hdmi-example/main.c
@@ -0,0 +1,259 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/videodev2.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#define ERRSTR strerror(errno)
+
+#define BYE_ON(cond, ...) \
+do { \
+ if (cond) { \
+ int errsv = errno; \
+ fprintf(stderr, "ERROR(%s:%d) : ", \
+ __FILE__, __LINE__); \
+ errno = errsv; \
+ fprintf(stderr, __VA_ARGS__); \
+ abort(); \
+ } \
+} while(0)
+
+#define BUFFER_CNT 3
+
+struct buffer {
+ int index;
+ void *data;
+ size_t size;
+ size_t width;
+ size_t height;
+
+ /* buffer state */
+ double t;
+};
+
+struct setup {
+ char *path;
+ int width;
+ int height;
+ int xoffset;
+ int yoffset;
+};
+
+struct context {
+ int fd;
+ struct buffer *buffer;
+ size_t buffer_cnt;
+};
+
+int parse_args(struct setup *setup, int argc, char *argv[]);
+
+int showtime(struct context *ctx);
+
+int main(int argc, char *argv[])
+{
+ int ret;
+
+ struct setup setup;
+ ret = parse_args(&setup, argc, argv);
+ BYE_ON(ret, "syntax error\n");
+
+ int fd;
+ fd = open(argv[1], O_RDWR);
+ BYE_ON(fd < 0, "open failed: %s\n", ERRSTR);
+
+ /* configure desired image size */
+ struct v4l2_format fmt;
+ fmt.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ fmt.fmt.pix.width = setup.width;
+ fmt.fmt.pix.height = setup.height;
+ /* format is hardcoded: draw procedures work only in 32-bit mode */
+ fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_BGR32;
+
+ ret = ioctl(fd, VIDIOC_S_FMT, &fmt);
+ BYE_ON(ret < 0, "VIDIOC_S_FMT failed: %s\n", ERRSTR);
+
+ /* update format struct to values adjusted by a driver */
+ ret = ioctl(fd, VIDIOC_G_FMT, &fmt);
+ BYE_ON(ret < 0, "VIDIOC_G_FMT failed: %s\n", ERRSTR);
+
+ /* allocate buffers */
+ struct v4l2_requestbuffers rqbufs;
+ rqbufs.count = BUFFER_CNT;
+ rqbufs.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ rqbufs.memory = V4L2_MEMORY_MMAP;
+
+ ret = ioctl(fd, VIDIOC_REQBUFS, &rqbufs);
+ BYE_ON(ret < 0, "VIDIOC_REQBUFS failed: %s\n", ERRSTR);
+ BYE_ON(rqbufs.count < BUFFER_CNT, "failed to get %d buffers\n",
+ BUFFER_CNT);
+
+ struct buffer buffer[BUFFER_CNT];
+ /* size_t size = 4 * setup.width * setup.height; */
+
+ /* buffers initalization */
+ for (int i = 0; i < BUFFER_CNT; ++i) {
+ struct v4l2_plane plane;
+ struct v4l2_buffer buf;
+ buf.index = i;
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ buf.memory = V4L2_MEMORY_MMAP;
+ buf.m.planes = &plane;
+ buf.length = 1;
+ /* get buffer properties from a driver */
+ ret = ioctl(fd, VIDIOC_QUERYBUF, &buf);
+ BYE_ON(ret < 0, "VIDIOC_QUERYBUF for buffer %d failed: %s\n",
+ buf.index, ERRSTR);
+
+ buffer[i].index = i;
+ /* mmap buffer to user space */
+ buffer[i].data = mmap(NULL, plane.length, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, plane.m.mem_offset);
+ BYE_ON(buffer[i].data == MAP_FAILED, "mmap failed: %s\n",
+ ERRSTR);
+ buffer[i].size = plane.length;
+ buffer[i].width = fmt.fmt.pix.width;
+ buffer[i].height = fmt.fmt.pix.height;
+ /* fill buffer with black */
+ for (size_t j = 0; 4 * j < buffer[i].size; ++j)
+ ((uint32_t*)buffer[i].data)[j] = 0xff000000;
+ }
+
+ /* crop output area on display */
+ struct v4l2_crop crop;
+ crop.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+ crop.c.left = setup.xoffset;
+ crop.c.top = setup.yoffset;
+ crop.c.width = setup.width;
+ crop.c.height = setup.height;
+ ret = ioctl(fd, VIDIOC_S_CROP, &crop);
+ BYE_ON(ret < 0, "VIDIOC_S_CROP failed: %s\n", ERRSTR);
+
+ struct context context;
+ context.fd = fd;
+ context.buffer = buffer;
+ context.buffer_cnt = BUFFER_CNT;
+ /* It's show-time !!! */
+ showtime(&context);
+
+ return 0;
+}
+
+int parse_args(struct setup *setup, int argc, char *argv[])
+{
+ setup->path = argv[1];
+ setup->width = atoi(argv[2]);
+ setup->height = atoi(argv[3]);
+ setup->xoffset = atoi(argv[4]);
+ setup->yoffset = atoi(argv[5]);
+ return 0;
+}
+
+double gettime(void);
+void buffer_fill(struct buffer *buf, double t);
+int queue(int fd, int index);
+int dequeue(int fd, int *index);
+
+int showtime(struct context *ctx)
+{
+ double t;
+
+ /* fill and pass all buffers to the driver */
+ for (int i = 0; i < ctx->buffer_cnt; ++i) {
+ t = gettime();
+ buffer_fill(&ctx->buffer[i], t);
+ queue(ctx->fd, i);
+ }
+ fprintf(stderr, "start\n");
+ /* start streaming */
+ int ret, type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ ret = ioctl(ctx->fd, VIDIOC_STREAMON, &type);
+ BYE_ON(ret, "VIDIOC_STREAMON failed: %s\n", ERRSTR);
+
+ int index;
+ /* main loop, every dequeued buffer is refilled and enqueued again */
+ while (dequeue(ctx->fd, &index) == 0) {
+ t = gettime();
+ buffer_fill(&ctx->buffer[index], t);
+ queue(ctx->fd, index);
+ }
+ return 0;
+}
+
+double gettime(void)
+{
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ double t = tv.tv_sec + 1e-6 * tv.tv_usec;
+ return t;
+}
+
+void draw_rect(struct buffer *buf, struct v4l2_rect *r, uint32_t v)
+{
+ uint32_t *ptr = buf->data;
+ ptr += buf->width * r->top + r->left;
+ for (int i = 0; i < r->height; ++i) {
+ for (int j = 0; j < r->width; ++j)
+ ptr[j] = v;
+ ptr += buf->width;
+ }
+}
+
+void prepare_rect(struct buffer *buf, struct v4l2_rect *r, double t)
+{
+ r->left = 0.8 * buf->width * (0.5 + 0.5 * sin(t));
+ r->top = 0.8 * buf->height * (0.5 + 0.5 * sin(1.41 * t));
+ r->width = 0.2 * buf->width;
+ r->height = 0.2 * buf->height;
+}
+
+void buffer_fill(struct buffer *buf, double t)
+{
+ struct v4l2_rect r;
+ prepare_rect(buf, &r, buf->t);
+ draw_rect(buf, &r, 0xff000000);
+ prepare_rect(buf, &r, t);
+ int R, G, B;
+ R = 125 + 125 * sin(3 * t);
+ G = 125 + 125 * sin(4 * t);
+ B = 125 + 125 * sin(5 * t);
+ draw_rect(buf, &r, (R << 0) | (G << 8) | (B << 16) | (0xff << 24));
+ buf->t = t;
+}
+
+int queue(int fd, int index)
+{
+ struct v4l2_buffer buf;
+ struct v4l2_plane plane;
+ memset(&buf, 0, sizeof buf);
+ memset(&plane, 0, sizeof plane);
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ buf.index = index;
+ buf.memory = V4L2_MEMORY_MMAP;
+ buf.m.planes = &plane;
+ buf.length = 1;
+ int ret;
+ ret = ioctl(fd, VIDIOC_QBUF, &buf);
+ BYE_ON(ret, "VIDIOC_QBUF(index = %d) failed: %s\n",
+ index, ERRSTR);
+ return 0;
+}
+
+int dequeue(int fd, int *index)
+{
+ int ret;
+ struct v4l2_buffer buf;
+ memset(&buf, 0, sizeof buf);
+ buf.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+ buf.memory = V4L2_MEMORY_MMAP;
+ ret = ioctl(fd, VIDIOC_DQBUF, &buf);
+ BYE_ON(ret, "VIDIOC_DQBUF failed: %s\n", ERRSTR);
+ *index = buf.index;
+ return 0;
+}

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