using namespace std;
using namespace std::placeholders;
-#define WIDTH 1280
-#define HEIGHT 750 /* 30 lines ancillary data? */
-//#define WIDTH 1920
-//#define HEIGHT 1125 /* ??? lines ancillary data? */
+#define MIN_WIDTH 640
#define HEADER_SIZE 44
//#define HEADER_SIZE 0
#define AUDIO_HEADER_SIZE 4
-//#define FRAME_SIZE (WIDTH * HEIGHT * 2 + HEADER_SIZE) // UYVY
-//#define FRAME_SIZE (WIDTH * HEIGHT * 2 * 4 / 3 + HEADER_SIZE) // v210
-#define FRAME_SIZE (8 << 20)
+#define FRAME_SIZE (8 << 20) // 8 MB.
+#define USB_VIDEO_TRANSFER_SIZE (128 << 10) // 128 kB.
+
+namespace {
FILE *audiofp;
thread usb_thread;
atomic<bool> should_quit;
+int find_xfer_size_for_width(int width)
+{
+ // Video seems to require isochronous packets scaled with the width;
+ // seemingly six lines is about right, rounded up to the required 1kB
+ // multiple.
+ int size = width * 2 * 6;
+ // Note that for 10-bit input, you'll need to increase size accordingly.
+ //size = size * 4 / 3;
+ if (size % 1024 != 0) {
+ size &= ~1023;
+ size += 1024;
+ }
+ return size;
+}
+
+void change_xfer_size_for_width(int width, libusb_transfer *xfr)
+{
+ assert(width >= MIN_WIDTH);
+ size_t size = find_xfer_size_for_width(width);
+ int num_iso_pack = xfr->length / size;
+ if (num_iso_pack != xfr->num_iso_packets ||
+ size != xfr->iso_packet_desc[0].length) {
+ xfr->num_iso_packets = num_iso_pack;
+ libusb_set_iso_packet_lengths(xfr, size);
+ }
+}
+
+} // namespace
+
FrameAllocator::~FrameAllocator() {}
// Audio is more important than video, and also much cheaper.
}
//dump_frame();
queue_frame(format, timecode, current_video_frame, &pending_video_frames);
+
+ // Update the assumed frame width. We might be one frame too late on format changes,
+ // but it's much better than asking the user to choose manually.
+ int width, height, frame_rate_nom, frame_rate_den;
+ bool interlaced;
+ if (decode_video_format(format, &width, &height, &frame_rate_nom, &frame_rate_den, &interlaced)) {
+ assumed_frame_width = width;
+ }
}
//printf("Found frame start, format 0x%04x timecode 0x%04x, previous frame length was %d/%d\n",
// format, timecode,
decode_packs(xfr, "DeckLinkAudioResyncT", 20, &usb->current_audio_frame, "audio", bind(&BMUSBCapture::start_new_audio_block, usb, _1));
} else {
decode_packs(xfr, "\x00\x00\xff\xff", 4, &usb->current_video_frame, "video", bind(&BMUSBCapture::start_new_frame, usb, _1));
+
+ // Update the transfer with the new assumed width, if we're in the process of changing formats.
+ change_xfer_size_for_width(usb->assumed_frame_width, xfr);
}
}
if (xfr->type == LIBUSB_TRANSFER_TYPE_CONTROL) {
//int num_transfers = (e == 3) ? 6 : 6;
int num_transfers = 10;
for (int i = 0; i < num_transfers; ++i) {
+ size_t buf_size;
int num_iso_pack, size;
if (e == 3) {
- // Video seems to require isochronous packets scaled with the width;
- // seemingly six lines is about right, rounded up to the required 1kB
- // multiple.
- size = WIDTH * 2 * 6;
- // Note that for 10-bit input, you'll need to increase size accordingly.
- //size = size * 4 / 3;
- if (size % 1024 != 0) {
- size &= ~1023;
- size += 1024;
- }
- num_iso_pack = (2 << 16) / size; // 128 kB.
- printf("Picking %d packets of 0x%x bytes each\n", num_iso_pack, size);
+ // Allocate for minimum width (because that will give us the most
+ // number of packets, so we don't need to reallocated, but we'll
+ // default to 720p for the first frame.
+ size = find_xfer_size_for_width(MIN_WIDTH);
+ num_iso_pack = USB_VIDEO_TRANSFER_SIZE / size;
+ buf_size = USB_VIDEO_TRANSFER_SIZE;
} else {
size = 0xc0;
num_iso_pack = 80;
+ buf_size = num_iso_pack * size;
}
- int num_bytes = num_iso_pack * size;
- uint8_t *buf = new uint8_t[num_bytes];
+ assert(size_t(num_iso_pack * size) <= buf_size);
+ uint8_t *buf = new uint8_t[buf_size];
xfr = libusb_alloc_transfer(num_iso_pack);
if (!xfr) {
}
int ep = LIBUSB_ENDPOINT_IN | e;
- libusb_fill_iso_transfer(xfr, devh, ep, buf, num_bytes,
+ libusb_fill_iso_transfer(xfr, devh, ep, buf, buf_size,
num_iso_pack, cb_xfr, nullptr, 0);
libusb_set_iso_packet_lengths(xfr, size);
xfr->user_data = this;
+
+ if (e == 3) {
+ change_xfer_size_for_width(assumed_frame_width, xfr);
+ }
+
iso_xfrs.push_back(xfr);
}
}
// No video signal. These green pseudo-frames seem to come at about 30.13 Hz.
// It's a strange thing, but what can you do.
// FIXME: find the dimensions.
+ *width = 720;
+ *height = 576;
*frame_rate_nom = 3013;
*frame_rate_den = 100;
return true;