diff options
Diffstat (limited to 'stream.c')
| -rw-r--r-- | stream.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/stream.c b/stream.c new file mode 100644 index 0000000..b6e0efe --- /dev/null +++ b/stream.c @@ -0,0 +1,250 @@ +/* + * UVC stream handling + * + * Copyright (C) 2010 Ideas on board SPRL <laurent.pinchart@ideasonboard.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "events.h" +#include "stream.h" +#include "uvc.h" +#include "v4l2.h" + +/* --------------------------------------------------------------------------- + * Video streaming + */ + +static void capture_video_process(void *d) +{ + struct uvc_stream *stream = d; + struct v4l2_video_buffer buf; + int ret; + + ret = v4l2_dequeue_buffer(stream->cap, &buf); + if (ret < 0) + return; + + v4l2_queue_buffer(stream->uvc->vdev, &buf); +} + +static void uvc_video_process(void *d) +{ + struct uvc_stream *stream = d; + struct v4l2_video_buffer buf; + int ret; + + ret = v4l2_dequeue_buffer(stream->uvc->vdev, &buf); + if (ret < 0) + return; + + v4l2_queue_buffer(stream->cap, &buf); +} + +static int uvc_video_enable(struct uvc_stream *stream, int enable) +{ + struct v4l2_device *cap = stream->cap; + struct uvc_device *dev = stream->uvc; + int ret; + + if (!enable) { + printf("Stopping video stream.\n"); + events_unwatch_fd(stream->events, dev->vdev->fd, EVENT_WRITE); + v4l2_stream_off(dev->vdev); + v4l2_free_buffers(dev->vdev); + return 0; + } + + printf("Starting video stream.\n"); + + ret = v4l2_alloc_buffers(dev->vdev, V4L2_MEMORY_DMABUF, 4); + if (ret < 0) { + printf("Failed to allocate buffers: %s (%d)\n", strerror(-ret), -ret); + return ret; + } + + ret = v4l2_import_buffers(dev->vdev, dev->vdev->nbufs, cap->buffers); + if (ret < 0) { + printf("Failed to import buffers: %s (%d)\n", strerror(-ret), -ret); + goto error; + } + + v4l2_stream_on(dev->vdev); + events_watch_fd(stream->events, dev->vdev->fd, EVENT_WRITE, + uvc_video_process, stream); + + return 0; + +error: + v4l2_free_buffers(dev->vdev); + return ret; +} + +static int capture_video_stream(struct uvc_stream *stream, int enable) +{ + struct v4l2_device *cap = stream->cap; + unsigned int i; + int ret; + + if (!enable) { + printf("Stopping video capture stream.\n"); + events_unwatch_fd(stream->events, cap->fd, EVENT_READ); + v4l2_stream_off(cap); + v4l2_free_buffers(cap); + return 0; + } + + printf("Starting video capture stream.\n"); + + ret = v4l2_alloc_buffers(cap, V4L2_MEMORY_MMAP, 4); + if (ret < 0) { + printf("Failed to allocate capture buffers.\n"); + return ret; + } + + ret = v4l2_export_buffers(cap); + if (ret < 0) { + printf("Failed to export buffers.\n"); + goto error; + } + + for (i = 0; i < cap->nbufs; ++i) { + struct v4l2_video_buffer *buf = &cap->buffers[i]; + + ret = v4l2_queue_buffer(cap, buf); + if (ret < 0) + goto error; + } + + v4l2_stream_on(cap); + events_watch_fd(stream->events, cap->fd, EVENT_READ, + capture_video_process, stream); + + return 0; + +error: + v4l2_free_buffers(cap); + return ret; +} + +void uvc_stream_enable(struct uvc_stream *stream, int enable) +{ + if (enable) { + capture_video_stream(stream, 1); + uvc_video_enable(stream, 1); + } else { + uvc_video_enable(stream, 0); + capture_video_stream(stream, 0); + } +} + +int uvc_stream_set_format(struct uvc_stream *stream) +{ + struct v4l2_device *cap = stream->cap; + struct uvc_device *dev = stream->uvc; + struct v4l2_pix_format fmt; + int ret; + + printf("Setting format to 0x%08x %ux%u\n", + dev->fcc, dev->width, dev->height); + + memset(&fmt, 0, sizeof fmt); + fmt.width = dev->width; + fmt.height = dev->height; + fmt.pixelformat = dev->fcc; + fmt.field = V4L2_FIELD_NONE; + if (dev->fcc == V4L2_PIX_FMT_MJPEG) + fmt.sizeimage = dev->maxsize * 1.5; + + ret = v4l2_set_format(dev->vdev, &fmt); + if (ret < 0) + return ret; + + return v4l2_set_format(cap, &fmt); +} + +static int uvc_video_init(struct uvc_device *dev __attribute__((__unused__))) +{ + return 0; +} + +/* --------------------------------------------------------------------------- + * Stream handling + */ + +struct uvc_stream *uvc_stream_new(const char *uvc_device, + const char *cap_device) +{ + struct uvc_stream *stream; + + stream = malloc(sizeof(*stream)); + if (stream == NULL) + return NULL; + + memset(stream, 0, sizeof(*stream)); + + stream->cap = v4l2_open(cap_device); + if (stream->cap == NULL) + goto error; + + stream->uvc = uvc_open(uvc_device); + if (stream->uvc == NULL) + goto error; + + return stream; + +error: + if (stream->cap) + v4l2_close(stream->cap); + + free(stream); + return NULL; +} + +void uvc_stream_delete(struct uvc_stream *stream) +{ + if (stream == NULL) + return; + + v4l2_close(stream->cap); + uvc_close(stream->uvc); + + free(stream); +} + +void uvc_stream_init_uvc(struct uvc_stream *stream, + struct uvc_function_config *fc) +{ + /* + * FIXME: The maximum size should be specified per format and frame. + */ + stream->uvc->maxsize = 0; + stream->uvc->fc = fc; + + uvc_events_init(stream->uvc); + uvc_video_init(stream->uvc); +} + +void uvc_stream_set_event_handler(struct uvc_stream *stream, + struct events *events) +{ + stream->events = events; + + events_watch_fd(stream->events, stream->uvc->vdev->fd, EVENT_EXCEPTION, + uvc_events_process, stream); +} |