git.sesse.net Git - bmusb/blob - bmusb.cpp

   1 // Intensity Shuttle USB3 prototype capture driver, v0.3
   2 // Can download 8-bit and 10-bit UYVY/v210 frames from HDMI, quite stable
   3 // (can do captures for hours at a time with no drops), except during startup
   4 // 576p60/720p60/1080i60 works, 1080p60 does not work (firmware limitation)
   5 // Audio comes out as 8-channel 24-bit raw audio.
   6
   7 #include <assert.h>
   8 #include <errno.h>
   9 #include <libusb.h>
  10 #include <netinet/in.h>
  11 #include <sched.h>
  12 #include <stdint.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #ifdef __SSE4_1__
  17 #include <immintrin.h>
  18 #endif
  19 #include "bmusb.h"
  20
  21 #include <algorithm>
  22 #include <atomic>
  23 #include <condition_variable>
  24 #include <cstddef>
  25 #include <cstdint>
  26 #include <deque>
  27 #include <functional>
  28 #include <memory>
  29 #include <mutex>
  30 #include <stack>
  31 #include <thread>
  32
  33 using namespace std;
  34 using namespace std::placeholders;
  35
  36 #define WIDTH 1280
  37 #define HEIGHT 750  /* 30 lines ancillary data? */
  38 //#define WIDTH 1920
  39 //#define HEIGHT 1125  /* ??? lines ancillary data? */
  40 #define HEADER_SIZE 44
  41 //#define HEADER_SIZE 0
  42 #define AUDIO_HEADER_SIZE 4
  43
  44 //#define FRAME_SIZE (WIDTH * HEIGHT * 2 + HEADER_SIZE)  // UYVY
  45 //#define FRAME_SIZE (WIDTH * HEIGHT * 2 * 4 / 3 + HEADER_SIZE)  // v210
  46 #define FRAME_SIZE (8 << 20)
  47
  48 FILE *audiofp;
  49
  50 thread usb_thread;
  51 atomic<bool> should_quit;
  52
  53 FrameAllocator::~FrameAllocator() {}
  54
  55 #define NUM_QUEUED_FRAMES 8
  56 class MallocFrameAllocator : public FrameAllocator {
  57 public:
  58         MallocFrameAllocator(size_t frame_size);
  59         Frame alloc_frame() override;
  60         void release_frame(Frame frame) override;
  61
  62 private:
  63         size_t frame_size;
  64
  65         mutex freelist_mutex;
  66         stack<unique_ptr<uint8_t[]>> freelist;  // All of size <frame_size>.
  67 };
  68
  69 MallocFrameAllocator::MallocFrameAllocator(size_t frame_size)
  70         : frame_size(frame_size)
  71 {
  72         for (int i = 0; i < NUM_QUEUED_FRAMES; ++i) {
  73                 freelist.push(unique_ptr<uint8_t[]>(new uint8_t[frame_size]));
  74         }
  75 }
  76
  77 FrameAllocator::Frame MallocFrameAllocator::alloc_frame()
  78 {
  79         Frame vf;
  80         vf.owner = this;
  81
  82         unique_lock<mutex> lock(freelist_mutex);  // Meh.
  83         if (freelist.empty()) {
  84                 printf("Frame overrun (no more spare frames of size %ld), dropping frame!\n",
  85                         frame_size);
  86         } else {
  87                 vf.data = freelist.top().release();
  88                 vf.size = frame_size;
  89                 freelist.pop();  // Meh.
  90         }
  91         return vf;
  92 }
  93
  94 void MallocFrameAllocator::release_frame(Frame frame)
  95 {
  96         unique_lock<mutex> lock(freelist_mutex);
  97         freelist.push(unique_ptr<uint8_t[]>(frame.data));
  98 }
  99
 100 bool uint16_less_than_with_wraparound(uint16_t a, uint16_t b)
 101 {
 102         if (a == b) {
 103                 return false;
 104         } else if (a < b) {
 105                 return (b - a < 0x8000);
 106         } else {
 107                 int wrap_b = 0x10000 + int(b);
 108                 return (wrap_b - a < 0x8000);
 109         }
 110 }
 111
 112 void BMUSBCapture::queue_frame(uint16_t format, uint16_t timecode, FrameAllocator::Frame frame, deque<QueuedFrame> *q)
 113 {
 114         if (!q->empty() && !uint16_less_than_with_wraparound(q->back().timecode, timecode)) {
 115                 printf("Blocks going backwards: prev=0x%04x, cur=0x%04x (dropped)\n",
 116                         q->back().timecode, timecode);
 117                 frame.owner->release_frame(frame);
 118                 return;
 119         }
 120
 121         QueuedFrame qf;
 122         qf.format = format;
 123         qf.timecode = timecode;
 124         qf.frame = frame;
 125
 126         {
 127                 unique_lock<mutex> lock(queue_lock);
 128                 q->push_back(move(qf));
 129         }
 130         queues_not_empty.notify_one();  // might be spurious
 131 }
 132
 133 void dump_frame(const char *filename, uint8_t *frame_start, size_t frame_len)
 134 {
 135         FILE *fp = fopen(filename, "wb");
 136         if (fwrite(frame_start + HEADER_SIZE, frame_len - HEADER_SIZE, 1, fp) != 1) {
 137                 printf("short write!\n");
 138         }
 139         fclose(fp);
 140 }
 141
 142 void dump_audio_block(uint8_t *audio_start, size_t audio_len)
 143 {
 144         fwrite(audio_start + AUDIO_HEADER_SIZE, 1, audio_len - AUDIO_HEADER_SIZE, audiofp);
 145 }
 146
 147 void BMUSBCapture::dequeue_thread()
 148 {
 149         for ( ;; ) {
 150                 unique_lock<mutex> lock(queue_lock);
 151                 queues_not_empty.wait(lock, [this]{ return !pending_video_frames.empty() && !pending_audio_frames.empty(); });
 152
 153                 uint16_t video_timecode = pending_video_frames.front().timecode;
 154                 uint16_t audio_timecode = pending_audio_frames.front().timecode;
 155                 if (video_timecode < audio_timecode) {
 156                         printf("Video block 0x%04x without corresponding audio block, dropping.\n",
 157                                 video_timecode);
 158                         video_frame_allocator->release_frame(pending_video_frames.front().frame);
 159                         pending_video_frames.pop_front();
 160                 } else if (audio_timecode < video_timecode) {
 161                         printf("Audio block 0x%04x without corresponding video block, dropping.\n",
 162                                 audio_timecode);
 163                         audio_frame_allocator->release_frame(pending_audio_frames.front().frame);
 164                         pending_audio_frames.pop_front();
 165                 } else {
 166                         QueuedFrame video_frame = pending_video_frames.front();
 167                         QueuedFrame audio_frame = pending_audio_frames.front();
 168                         pending_audio_frames.pop_front();
 169                         pending_video_frames.pop_front();
 170                         lock.unlock();
 171
 172 #if 0
 173                         char filename[255];
 174                         snprintf(filename, sizeof(filename), "%04x%04x.uyvy", video_frame.format, video_timecode);
 175                         dump_frame(filename, video_frame.frame.data, video_frame.data_len);
 176                         dump_audio_block(audio_frame.frame.data, audio_frame.data_len);
 177 #endif
 178
 179                         frame_callback(video_timecode,
 180                                        video_frame.frame, HEADER_SIZE, video_frame.format,
 181                                        audio_frame.frame, AUDIO_HEADER_SIZE, audio_frame.format);
 182                 }
 183         }
 184 }
 185
 186 void BMUSBCapture::start_new_frame(const uint8_t *start)
 187 {
 188         uint16_t format = (start[3] << 8) | start[2];
 189         uint16_t timecode = (start[1] << 8) | start[0];
 190
 191         if (current_video_frame.len > 0) {
 192                 //dump_frame();
 193                 queue_frame(format, timecode, current_video_frame, &pending_video_frames);
 194         }
 195         //printf("Found frame start, format 0x%04x timecode 0x%04x, previous frame length was %d/%d\n",
 196         //      format, timecode,
 197         //      //start[7], start[6], start[5], start[4],
 198         //      read_current_frame, FRAME_SIZE);
 199
 200         current_video_frame = video_frame_allocator->alloc_frame();
 201         //if (current_video_frame.data == nullptr) {
 202         //      read_current_frame = -1;
 203         //} else {
 204         //      read_current_frame = 0;
 205         //}
 206 }
 207
 208 void BMUSBCapture::start_new_audio_block(const uint8_t *start)
 209 {
 210         uint16_t format = (start[3] << 8) | start[2];
 211         uint16_t timecode = (start[1] << 8) | start[0];
 212         if (current_audio_frame.len > 0) {
 213                 //dump_audio_block();
 214                 queue_frame(format, timecode, current_audio_frame, &pending_audio_frames);
 215         }
 216         //printf("Found audio block start, format 0x%04x timecode 0x%04x, previous block length was %d\n",
 217         //      format, timecode, read_current_audio_block);
 218         current_audio_frame = audio_frame_allocator->alloc_frame();
 219 }
 220
 221 #if 0
 222 static void dump_pack(const libusb_transfer *xfr, int offset, const libusb_iso_packet_descriptor *pack)
 223 {
 224         //      printf("ISO pack%u length:%u, actual_length:%u, offset:%u\n", i, pack->length, pack->actual_length, offset);
 225         for (unsigned j = 0; j < pack->actual_length; j++) {
 226         //for (int j = 0; j < min(pack->actual_length, 16u); j++) {
 227                 printf("%02x", xfr->buffer[j + offset]);
 228                 if ((j % 16) == 15)
 229                         printf("\n");
 230                 else if ((j % 8) == 7)
 231                         printf("  ");
 232                 else
 233                         printf(" ");
 234         }
 235 }
 236 #endif
 237
 238 void memcpy_interleaved(uint8_t *dest1, uint8_t *dest2, const uint8_t *src, size_t n)
 239 {
 240         assert(n % 2 == 0);
 241         uint8_t *dptr1 = dest1;
 242         uint8_t *dptr2 = dest2;
 243
 244         for (size_t i = 0; i < n; i += 2) {
 245                 *dptr1++ = *src++;
 246                 *dptr2++ = *src++;
 247         }
 248 }
 249
 250 void add_to_frame(FrameAllocator::Frame *current_frame, const char *frame_type_name, const uint8_t *start, const uint8_t *end)
 251 {
 252         if (current_frame->data == nullptr ||
 253             current_frame->len > current_frame->size ||
 254             start == end) {
 255                 return;
 256         }
 257
 258         int bytes = end - start;
 259         if (current_frame->len + bytes > current_frame->size) {
 260                 printf("%d bytes overflow after last %s frame\n",
 261                         int(current_frame->len + bytes - current_frame->size), frame_type_name);
 262                 //dump_frame();
 263         } else {
 264                 if (current_frame->interleaved) {
 265                         uint8_t *data = current_frame->data + current_frame->len / 2;
 266                         uint8_t *data2 = current_frame->data2 + current_frame->len / 2;
 267                         if (current_frame->len % 2 == 1) {
 268                                 ++data;
 269                                 swap(data, data2);
 270                         }
 271                         if (bytes % 2 == 1) {
 272                                 *data++ = *start++;
 273                                 swap(data, data2);
 274                                 ++current_frame->len;
 275                                 --bytes;
 276                         }
 277                         memcpy_interleaved(data, data2, start, bytes);
 278                         current_frame->len += bytes;
 279                 } else {
 280                         memcpy(current_frame->data + current_frame->len, start, bytes);
 281                         current_frame->len += bytes;
 282                 }
 283         }
 284 }
 285
 286 #ifdef __SSE4_1__
 287
 288 #if 0
 289 void avx2_dump(const char *name, __m256i n)
 290 {
 291         printf("%-10s:", name);
 292         printf(" %02x", _mm256_extract_epi8(n, 0));
 293         printf(" %02x", _mm256_extract_epi8(n, 1));
 294         printf(" %02x", _mm256_extract_epi8(n, 2));
 295         printf(" %02x", _mm256_extract_epi8(n, 3));
 296         printf(" %02x", _mm256_extract_epi8(n, 4));
 297         printf(" %02x", _mm256_extract_epi8(n, 5));
 298         printf(" %02x", _mm256_extract_epi8(n, 6));
 299         printf(" %02x", _mm256_extract_epi8(n, 7));
 300         printf(" ");
 301         printf(" %02x", _mm256_extract_epi8(n, 8));
 302         printf(" %02x", _mm256_extract_epi8(n, 9));
 303         printf(" %02x", _mm256_extract_epi8(n, 10));
 304         printf(" %02x", _mm256_extract_epi8(n, 11));
 305         printf(" %02x", _mm256_extract_epi8(n, 12));
 306         printf(" %02x", _mm256_extract_epi8(n, 13));
 307         printf(" %02x", _mm256_extract_epi8(n, 14));
 308         printf(" %02x", _mm256_extract_epi8(n, 15));
 309         printf(" ");
 310         printf(" %02x", _mm256_extract_epi8(n, 16));
 311         printf(" %02x", _mm256_extract_epi8(n, 17));
 312         printf(" %02x", _mm256_extract_epi8(n, 18));
 313         printf(" %02x", _mm256_extract_epi8(n, 19));
 314         printf(" %02x", _mm256_extract_epi8(n, 20));
 315         printf(" %02x", _mm256_extract_epi8(n, 21));
 316         printf(" %02x", _mm256_extract_epi8(n, 22));
 317         printf(" %02x", _mm256_extract_epi8(n, 23));
 318         printf(" ");
 319         printf(" %02x", _mm256_extract_epi8(n, 24));
 320         printf(" %02x", _mm256_extract_epi8(n, 25));
 321         printf(" %02x", _mm256_extract_epi8(n, 26));
 322         printf(" %02x", _mm256_extract_epi8(n, 27));
 323         printf(" %02x", _mm256_extract_epi8(n, 28));
 324         printf(" %02x", _mm256_extract_epi8(n, 29));
 325         printf(" %02x", _mm256_extract_epi8(n, 30));
 326         printf(" %02x", _mm256_extract_epi8(n, 31));
 327         printf("\n");
 328 }
 329 #endif
 330
 331 // Does a memcpy and memchr in one to reduce processing time.
 332 // Note that the benefit is somewhat limited if your L3 cache is small,
 333 // as you'll (unfortunately) spend most of the time loading the data
 334 // from main memory.
 335 //
 336 // Complicated cases are left to the slow path; it basically stops copying
 337 // up until the first instance of "sync_char" (usually a bit before, actually).
 338 // This is fine, since 0x00 bytes shouldn't really show up in normal picture
 339 // data, and what we really need this for is the 00 00 ff ff marker in video data.
 340 const uint8_t *add_to_frame_fastpath(FrameAllocator::Frame *current_frame, const uint8_t *start, const uint8_t *limit, const char sync_char)
 341 {
 342         if (current_frame->data == nullptr ||
 343             current_frame->len > current_frame->size ||
 344             start == limit) {
 345                 return start;
 346         }
 347         size_t orig_bytes = limit - start;
 348         if (orig_bytes < 128) {
 349                 // Don't bother.
 350                 return start;
 351         }
 352
 353         // Don't read more bytes than we can write.
 354         limit = min(limit, start + (current_frame->size - current_frame->len));
 355
 356         // Align end to 32 bytes.
 357         limit = (const uint8_t *)(intptr_t(limit) & ~31);
 358
 359         if (start >= limit) {
 360                 return start;
 361         }
 362
 363         // Process [0,31] bytes, such that start gets aligned to 32 bytes.
 364         const uint8_t *aligned_start = (const uint8_t *)(intptr_t(start + 31) & ~31);
 365         if (aligned_start != start) {
 366                 const uint8_t *sync_start = (const uint8_t *)memchr(start, sync_char, aligned_start - start);
 367                 if (sync_start == nullptr) {
 368                         add_to_frame(current_frame, "", start, aligned_start);
 369                 } else {
 370                         add_to_frame(current_frame, "", start, sync_start);
 371                         return sync_start;
 372                 }
 373         }
 374
 375         // Make the length a multiple of 64.
 376         if (current_frame->interleaved) {
 377                 if (((limit - aligned_start) % 64) != 0) {
 378                         limit -= 32;
 379                 }
 380                 assert(((limit - aligned_start) % 64) == 0);
 381         }
 382
 383 #if __AVX2__
 384         const __m256i needle = _mm256_set1_epi8(sync_char);
 385
 386         const __restrict __m256i *in = (const __m256i *)aligned_start;
 387         if (current_frame->interleaved) {
 388                 __restrict __m256i *out1 = (__m256i *)(current_frame->data + (current_frame->len + 1) / 2);
 389                 __restrict __m256i *out2 = (__m256i *)(current_frame->data2 + current_frame->len / 2);
 390                 if (current_frame->len % 2 == 1) {
 391                         swap(out1, out2);
 392                 }
 393
 394                 __m256i shuffle_cw = _mm256_set_epi8(
 395                         15, 13, 11, 9, 7, 5, 3, 1, 14, 12, 10, 8, 6, 4, 2, 0,
 396                         15, 13, 11, 9, 7, 5, 3, 1, 14, 12, 10, 8, 6, 4, 2, 0);
 397                 while (in < (const __m256i *)limit) {
 398                         // Note: For brevity, comments show lanes as if they were 2x64-bit (they're actually 2x128).
 399                         __m256i data1 = _mm256_stream_load_si256(in);         // AaBbCcDd EeFfGgHh
 400                         __m256i data2 = _mm256_stream_load_si256(in + 1);     // IiJjKkLl MmNnOoPp
 401
 402                         __m256i found1 = _mm256_cmpeq_epi8(data1, needle);
 403                         __m256i found2 = _mm256_cmpeq_epi8(data2, needle);
 404                         __m256i found = _mm256_or_si256(found1, found2);
 405
 406                         data1 = _mm256_shuffle_epi8(data1, shuffle_cw);       // ABCDabcd EFGHefgh
 407                         data2 = _mm256_shuffle_epi8(data2, shuffle_cw);       // IJKLijkl MNOPmnop
 408
 409                         data1 = _mm256_permute4x64_epi64(data1, 0b11011000);  // ABCDEFGH abcdefgh
 410                         data2 = _mm256_permute4x64_epi64(data2, 0b11011000);  // IJKLMNOP ijklmnop
 411
 412                         __m256i lo = _mm256_permute2x128_si256(data1, data2, 0b00100000);
 413                         __m256i hi = _mm256_permute2x128_si256(data1, data2, 0b00110001);
 414
 415                         _mm256_storeu_si256(out1, lo);  // Store as early as possible, even if the data isn't used.
 416                         _mm256_storeu_si256(out2, hi);
 417
 418                         if (!_mm256_testz_si256(found, found)) {
 419                                 break;
 420                         }
 421
 422                         in += 2;
 423                         ++out1;
 424                         ++out2;
 425                 }
 426                 current_frame->len += (uint8_t *)in - aligned_start;
 427         } else {
 428                 __m256i *out = (__m256i *)(current_frame->data + current_frame->len);
 429                 while (in < (const __m256i *)limit) {
 430                         __m256i data = _mm256_load_si256(in);
 431                         _mm256_storeu_si256(out, data);  // Store as early as possible, even if the data isn't used.
 432                         __m256i found = _mm256_cmpeq_epi8(data, needle);
 433                         if (!_mm256_testz_si256(found, found)) {
 434                                 break;
 435                         }
 436
 437                         ++in;
 438                         ++out;
 439                 }
 440                 current_frame->len = (uint8_t *)out - current_frame->data;
 441         }
 442 #else
 443         const __m128i needle = _mm_set1_epi8(sync_char);
 444
 445         const __m128i *in = (const __m128i *)aligned_start;
 446         if (current_frame->interleaved) {
 447                 __m128i *out1 = (__m128i *)(current_frame->data + (current_frame->len + 1) / 2);
 448                 __m128i *out2 = (__m128i *)(current_frame->data2 + current_frame->len / 2);
 449                 if (current_frame->len % 2 == 1) {
 450                         swap(out1, out2);
 451                 }
 452
 453                 __m128i mask_lower_byte = _mm_set1_epi16(0x00ff);
 454                 while (in < (const __m128i *)limit) {
 455                         __m128i data1 = _mm_load_si128(in);
 456                         __m128i data2 = _mm_load_si128(in + 1);
 457                         __m128i data1_lo = _mm_and_si128(data1, mask_lower_byte);
 458                         __m128i data2_lo = _mm_and_si128(data2, mask_lower_byte);
 459                         __m128i data1_hi = _mm_srli_epi16(data1, 8);
 460                         __m128i data2_hi = _mm_srli_epi16(data2, 8);
 461                         __m128i lo = _mm_packus_epi16(data1_lo, data2_lo);
 462                         _mm_storeu_si128(out1, lo);  // Store as early as possible, even if the data isn't used.
 463                         __m128i hi = _mm_packus_epi16(data1_hi, data2_hi);
 464                         _mm_storeu_si128(out2, hi);
 465                         __m128i found1 = _mm_cmpeq_epi8(data1, needle);
 466                         __m128i found2 = _mm_cmpeq_epi8(data2, needle);
 467                         if (!_mm_testz_si128(found1, found1) ||
 468                             !_mm_testz_si128(found2, found2)) {
 469                                 break;
 470                         }
 471
 472                         in += 2;
 473                         ++out1;
 474                         ++out2;
 475                 }
 476                 current_frame->len += (uint8_t *)in - aligned_start;
 477         } else {
 478                 __m128i *out = (__m128i *)(current_frame->data + current_frame->len);
 479                 while (in < (const __m128i *)limit) {
 480                         __m128i data = _mm_load_si128(in);
 481                         _mm_storeu_si128(out, data);  // Store as early as possible, even if the data isn't used.
 482                         __m128i found = _mm_cmpeq_epi8(data, needle);
 483                         if (!_mm_testz_si128(found, found)) {
 484                                 break;
 485                         }
 486
 487                         ++in;
 488                         ++out;
 489                 }
 490                 current_frame->len = (uint8_t *)out - current_frame->data;
 491         }
 492 #endif
 493
 494         //printf("managed to fastpath %ld/%ld bytes\n", (const uint8_t *)in - (const uint8_t *)aligned_start, orig_bytes);
 495
 496         return (const uint8_t *)in;
 497 }
 498 #endif
 499
 500 void decode_packs(const libusb_transfer *xfr,
 501                   const char *sync_pattern,
 502                   int sync_length,
 503                   FrameAllocator::Frame *current_frame,
 504                   const char *frame_type_name,
 505                   function<void(const uint8_t *start)> start_callback)
 506 {
 507         int offset = 0;
 508         for (int i = 0; i < xfr->num_iso_packets; i++) {
 509                 const libusb_iso_packet_descriptor *pack = &xfr->iso_packet_desc[i];
 510
 511                 if (pack->status != LIBUSB_TRANSFER_COMPLETED) {
 512                         fprintf(stderr, "Error: pack %u/%u status %d\n", i, xfr->num_iso_packets, pack->status);
 513                         continue;
 514 //exit(5);
 515                 }
 516
 517                 const uint8_t *start = xfr->buffer + offset;
 518                 const uint8_t *limit = start + pack->actual_length;
 519                 while (start < limit) {  // Usually runs only one iteration.
 520 #ifdef __SSE4_1__
 521                         start = add_to_frame_fastpath(current_frame, start, limit, sync_pattern[0]);
 522                         if (start == limit) break;
 523                         assert(start < limit);
 524 #endif
 525
 526                         const unsigned char* start_next_frame = (const unsigned char *)memmem(start, limit - start, sync_pattern, sync_length);
 527                         if (start_next_frame == nullptr) {
 528                                 // add the rest of the buffer
 529                                 add_to_frame(current_frame, frame_type_name, start, limit);
 530                                 break;
 531                         } else {
 532                                 add_to_frame(current_frame, frame_type_name, start, start_next_frame);
 533                                 start = start_next_frame + sync_length;  // skip sync
 534                                 start_callback(start);
 535                         }
 536                 }
 537 #if 0
 538                 dump_pack(xfr, offset, pack);
 539 #endif
 540                 offset += pack->length;
 541         }
 542 }
 543
 544 void BMUSBCapture::cb_xfr(struct libusb_transfer *xfr)
 545 {
 546         if (xfr->status != LIBUSB_TRANSFER_COMPLETED) {
 547                 fprintf(stderr, "transfer status %d\n", xfr->status);
 548                 libusb_free_transfer(xfr);
 549                 exit(3);
 550         }
 551
 552         assert(xfr->user_data != nullptr);
 553         BMUSBCapture *usb = static_cast<BMUSBCapture *>(xfr->user_data);
 554
 555         if (xfr->type == LIBUSB_TRANSFER_TYPE_ISOCHRONOUS) {
 556                 if (xfr->endpoint == 0x84) {
 557                         decode_packs(xfr, "DeckLinkAudioResyncT", 20, &usb->current_audio_frame, "audio", bind(&BMUSBCapture::start_new_audio_block, usb, _1));
 558                 } else {
 559                         decode_packs(xfr, "\x00\x00\xff\xff", 4, &usb->current_video_frame, "video", bind(&BMUSBCapture::start_new_frame, usb, _1));
 560                 }
 561         }
 562         if (xfr->type == LIBUSB_TRANSFER_TYPE_CONTROL) {
 563                 //const libusb_control_setup *setup = libusb_control_transfer_get_setup(xfr);
 564                 uint8_t *buf = libusb_control_transfer_get_data(xfr);
 565 #if 0
 566                 if (setup->wIndex == 44) {
 567                         printf("read timer register: 0x%02x%02x%02x%02x\n", buf[0], buf[1], buf[2], buf[3]);
 568                 } else {
 569                         printf("read register %2d:                      0x%02x%02x%02x%02x\n",
 570                                 setup->wIndex, buf[0], buf[1], buf[2], buf[3]);
 571                 }
 572 #else
 573                 memcpy(usb->register_file + usb->current_register, buf, 4);
 574                 usb->current_register = (usb->current_register + 4) % NUM_BMUSB_REGISTERS;
 575                 if (usb->current_register == 0) {
 576                         // read through all of them
 577                         printf("register dump:");
 578                         for (int i = 0; i < NUM_BMUSB_REGISTERS; i += 4) {
 579                                 printf(" 0x%02x%02x%02x%02x", usb->register_file[i], usb->register_file[i + 1], usb->register_file[i + 2], usb->register_file[i + 3]);
 580                         }
 581                         printf("\n");
 582                 }
 583                 libusb_fill_control_setup(xfr->buffer,
 584                     LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN, /*request=*/214, /*value=*/0,
 585                         /*index=*/usb->current_register, /*length=*/4);
 586 #endif
 587         }
 588
 589 #if 0
 590         printf("length:%u, actual_length:%u\n", xfr->length, xfr->actual_length);
 591         for (i = 0; i < xfr->actual_length; i++) {
 592                 printf("%02x", xfr->buffer[i]);
 593                 if (i % 16)
 594                         printf("\n");
 595                 else if (i % 8)
 596                         printf("  ");
 597                 else
 598                         printf(" ");
 599         }
 600 #endif
 601
 602         if (libusb_submit_transfer(xfr) < 0) {
 603                 fprintf(stderr, "error re-submitting URB\n");
 604                 exit(1);
 605         }
 606 }
 607
 608 void BMUSBCapture::usb_thread_func()
 609 {
 610         printf("usb thread started\n");
 611
 612         sched_param param;
 613         memset(&param, 0, sizeof(param));
 614         param.sched_priority = 1;
 615         if (sched_setscheduler(0, SCHED_RR, &param) == -1) {
 616                 printf("couldn't set realtime priority for USB thread: %s\n", strerror(errno));
 617         }
 618         while (!should_quit) {
 619                 int rc = libusb_handle_events(nullptr);
 620                 if (rc != LIBUSB_SUCCESS)
 621                         break;
 622         }
 623 }
 624
 625 void BMUSBCapture::configure_card()
 626 {
 627         if (video_frame_allocator == nullptr) {
 628                 set_video_frame_allocator(new MallocFrameAllocator(FRAME_SIZE));  // FIXME: leak.
 629         }
 630         if (audio_frame_allocator == nullptr) {
 631                 set_audio_frame_allocator(new MallocFrameAllocator(65536));  // FIXME: leak.
 632         }
 633         thread(&BMUSBCapture::dequeue_thread, this).detach();
 634
 635         int rc;
 636         struct libusb_transfer *xfr;
 637
 638         rc = libusb_init(nullptr);
 639         if (rc < 0) {
 640                 fprintf(stderr, "Error initializing libusb: %s\n", libusb_error_name(rc));
 641                 exit(1);
 642         }
 643
 644         //struct libusb_device_handle *devh = libusb_open_device_with_vid_pid(nullptr, 0x1edb, 0xbd3b);
 645         //struct libusb_device_handle *devh = libusb_open_device_with_vid_pid(nullptr, 0x1edb, 0xbd4f);
 646         struct libusb_device_handle *devh = libusb_open_device_with_vid_pid(nullptr, vid, pid);
 647         if (!devh) {
 648                 fprintf(stderr, "Error finding USB device\n");
 649                 exit(1);
 650         }
 651
 652         libusb_config_descriptor *config;
 653         rc = libusb_get_config_descriptor(libusb_get_device(devh), /*config_index=*/0, &config);
 654         if (rc < 0) {
 655                 fprintf(stderr, "Error getting configuration: %s\n", libusb_error_name(rc));
 656                 exit(1);
 657         }
 658         printf("%d interface\n", config->bNumInterfaces);
 659         for (int interface_number = 0; interface_number < config->bNumInterfaces; ++interface_number) {
 660                 printf("  interface %d\n", interface_number);
 661                 const libusb_interface *interface = &config->interface[interface_number];
 662                 for (int altsetting = 0; altsetting < interface->num_altsetting; ++altsetting) {
 663                         const libusb_interface_descriptor *interface_desc = &interface->altsetting[altsetting];
 664                         printf("    alternate setting %d\n", interface_desc->bAlternateSetting);
 665                         for (int endpoint_number = 0; endpoint_number < interface_desc->bNumEndpoints; ++endpoint_number) {
 666                                 const libusb_endpoint_descriptor *endpoint = &interface_desc->endpoint[endpoint_number];
 667                                 printf("        endpoint address 0x%02x\n", endpoint->bEndpointAddress);
 668                         }
 669                 }
 670         }
 671
 672         rc = libusb_set_configuration(devh, /*configuration=*/1);
 673         if (rc < 0) {
 674                 fprintf(stderr, "Error setting configuration 1: %s\n", libusb_error_name(rc));
 675                 exit(1);
 676         }
 677
 678         rc = libusb_claim_interface(devh, 0);
 679         if (rc < 0) {
 680                 fprintf(stderr, "Error claiming interface 0: %s\n", libusb_error_name(rc));
 681                 exit(1);
 682         }
 683
 684         // Alternate setting 1 is output, alternate setting 2 is input.
 685         // Card is reset when switching alternates, so the driver uses
 686         // this “double switch” when it wants to reset.
 687         rc = libusb_set_interface_alt_setting(devh, /*interface=*/0, /*alternate_setting=*/1);
 688         if (rc < 0) {
 689                 fprintf(stderr, "Error setting alternate 1: %s\n", libusb_error_name(rc));
 690                 exit(1);
 691         }
 692         rc = libusb_set_interface_alt_setting(devh, /*interface=*/0, /*alternate_setting=*/2);
 693         if (rc < 0) {
 694                 fprintf(stderr, "Error setting alternate 1: %s\n", libusb_error_name(rc));
 695                 exit(1);
 696         }
 697 #if 0
 698         rc = libusb_set_interface_alt_setting(devh, /*interface=*/0, /*alternate_setting=*/1);
 699         if (rc < 0) {
 700                 fprintf(stderr, "Error setting alternate 1: %s\n", libusb_error_name(rc));
 701                 exit(1);
 702         }
 703 #endif
 704
 705 #if 0
 706         rc = libusb_claim_interface(devh, 3);
 707         if (rc < 0) {
 708                 fprintf(stderr, "Error claiming interface 3: %s\n", libusb_error_name(rc));
 709                 exit(1);
 710         }
 711 #endif
 712
 713         // theories:
 714         //   44 is some kind of timer register (first 16 bits count upwards)
 715         //   24 is some sort of watchdog?
 716         //      you can seemingly set it to 0x73c60001 and that bit will eventually disappear
 717         //      (or will go to 0x73c60010?), also seen 0x73c60100
 718         //   12 also changes all the time, unclear why
 719         //   16 seems to be autodetected mode somehow
 720         //      --    this is e00115e0 after reset?
 721         //                    ed0115e0 after mode change [to output?]
 722         //                    2d0015e0 after more mode change [to input]
 723         //                    ed0115e0 after more mode change
 724         //                    2d0015e0 after more mode change
 725         //
 726         //                    390115e0 seems to indicate we have signal
 727         //         changes to 200115e0 when resolution changes/we lose signal, driver resets after a while
 728         //
 729         //                    200015e0 on startup
 730         //         changes to 250115e0 when we sync to the signal
 731         //
 732         //    so only first 16 bits count, and 0x0100 is a mask for ok/stable signal?
 733         //
 734         //    Bottom 16 bits of this register seem to be firmware version number (possibly not all all of them).
 735         //
 736         //    28 and 32 seems to be analog audio input levels (one byte for each of the eight channels).
 737         //    however, if setting 32 with HDMI embedded audio, it is immediately overwritten back (to 0xe137002a).
 738         //
 739         //    4, 8, 20 are unclear. seem to be some sort of bitmask, but we can set them to 0 with no apparent effect.
 740         //    perhaps some of them are related to analog output?
 741         //
 742         //    36 can be set to 0 with no apparent effect (all of this tested on both video and audio),
 743         //    but the driver sets it to 0x8036802a at some point.
 744         //
 745         //    all of this is on request 214/215. other requests (192, 219,
 746         //    222, 223, 224) are used for firmware upgrade. Probably best to
 747         //    stay out of it unless you know what you're doing.
 748         //
 749         //
 750         // register 16:
 751         // first byte is 0x39 for a stable 576p60 signal, 0x2d for a stable 720p60 signal, 0x20 for no signal
 752         //
 753         // theories:
 754         //   0x01 - stable signal
 755         //   0x04 - deep color
 756         //   0x08 - unknown (audio??)
 757         //   0x20 - 720p??
 758         //   0x30 - 576p??
 759
 760         struct ctrl {
 761                 int endpoint;
 762                 int request;
 763                 int index;
 764                 uint32_t data;
 765         };
 766         static const ctrl ctrls[] = {
 767                 { LIBUSB_ENDPOINT_IN,  214, 16, 0 },
 768                 { LIBUSB_ENDPOINT_IN,  214,  0, 0 },
 769
 770                 // seems to capture on HDMI, clearing the 0x20000000 bit seems to activate 10-bit
 771                 // capture (v210).
 772                 // clearing the 0x08000000 bit seems to change the capture format (other source?)
 773                 // 0x10000000 = analog audio instead of embedded audio, it seems
 774                 // 0x3a000000 = component video? (analog audio)
 775                 // 0x3c000000 = composite video? (analog audio)
 776                 // 0x3e000000 = s-video? (analog audio)
 777                 { LIBUSB_ENDPOINT_OUT, 215,  0, 0x29000000 },
 778                 //{ LIBUSB_ENDPOINT_OUT, 215,  0, 0x80000100 },
 779                 //{ LIBUSB_ENDPOINT_OUT, 215,  0, 0x09000000 },
 780                 { LIBUSB_ENDPOINT_OUT, 215, 24, 0x73c60001 },  // latch for frame start?
 781                 { LIBUSB_ENDPOINT_IN,  214, 24, 0 },  //
 782         };
 783
 784         for (unsigned req = 0; req < sizeof(ctrls) / sizeof(ctrls[0]); ++req) {
 785                 uint32_t flipped = htonl(ctrls[req].data);
 786                 static uint8_t value[4];
 787                 memcpy(value, &flipped, sizeof(flipped));
 788                 int size = sizeof(value);
 789                 //if (ctrls[req].request == 215) size = 0;
 790                 rc = libusb_control_transfer(devh, LIBUSB_REQUEST_TYPE_VENDOR | ctrls[req].endpoint,
 791                         /*request=*/ctrls[req].request, /*value=*/0, /*index=*/ctrls[req].index, value, size, /*timeout=*/0);
 792                 if (rc < 0) {
 793                         fprintf(stderr, "Error on control %d: %s\n", ctrls[req].index, libusb_error_name(rc));
 794                         exit(1);
 795                 }
 796
 797                 printf("rc=%d: ep=%d@%d %d -> 0x", rc, ctrls[req].endpoint, ctrls[req].request, ctrls[req].index);
 798                 for (int i = 0; i < rc; ++i) {
 799                         printf("%02x", value[i]);
 800                 }
 801                 printf("\n");
 802         }
 803
 804 #if 0
 805         // DEBUG
 806         for ( ;; ) {
 807                 static int my_index = 0;
 808                 static uint8_t value[4];
 809                 int size = sizeof(value);
 810                 rc = libusb_control_transfer(devh, LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN,
 811                         /*request=*/214, /*value=*/0, /*index=*/my_index, value, size, /*timeout=*/0);
 812                 if (rc < 0) {
 813                         fprintf(stderr, "Error on control\n");
 814                         exit(1);
 815                 }
 816                 printf("rc=%d index=%d: 0x", rc, my_index);
 817                 for (int i = 0; i < rc; ++i) {
 818                         printf("%02x", value[i]);
 819                 }
 820                 printf("\n");
 821         }
 822 #endif
 823
 824 #if 0
 825         // set up an asynchronous transfer of the timer register
 826         static uint8_t cmdbuf[LIBUSB_CONTROL_SETUP_SIZE + 4];
 827         static int completed = 0;
 828
 829         xfr = libusb_alloc_transfer(0);
 830         libusb_fill_control_setup(cmdbuf,
 831             LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN, /*request=*/214, /*value=*/0,
 832                 /*index=*/44, /*length=*/4);
 833         libusb_fill_control_transfer(xfr, devh, cmdbuf, cb_xfr, &completed, 0);
 834         xfr->user_data = this;
 835         libusb_submit_transfer(xfr);
 836
 837         // set up an asynchronous transfer of register 24
 838         static uint8_t cmdbuf2[LIBUSB_CONTROL_SETUP_SIZE + 4];
 839         static int completed2 = 0;
 840
 841         xfr = libusb_alloc_transfer(0);
 842         libusb_fill_control_setup(cmdbuf2,
 843             LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN, /*request=*/214, /*value=*/0,
 844                 /*index=*/24, /*length=*/4);
 845         libusb_fill_control_transfer(xfr, devh, cmdbuf2, cb_xfr, &completed2, 0);
 846         xfr->user_data = this;
 847         libusb_submit_transfer(xfr);
 848 #endif
 849
 850         // set up an asynchronous transfer of the register dump
 851         static uint8_t cmdbuf3[LIBUSB_CONTROL_SETUP_SIZE + 4];
 852         static int completed3 = 0;
 853
 854         xfr = libusb_alloc_transfer(0);
 855         libusb_fill_control_setup(cmdbuf3,
 856             LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN, /*request=*/214, /*value=*/0,
 857                 /*index=*/current_register, /*length=*/4);
 858         libusb_fill_control_transfer(xfr, devh, cmdbuf3, cb_xfr, &completed3, 0);
 859         xfr->user_data = this;
 860         //libusb_submit_transfer(xfr);
 861
 862         audiofp = fopen("audio.raw", "wb");
 863
 864         // set up isochronous transfers for audio and video
 865         for (int e = 3; e <= 4; ++e) {
 866                 //int num_transfers = (e == 3) ? 6 : 6;
 867                 int num_transfers = 6;
 868                 for (int i = 0; i < num_transfers; ++i) {
 869                         int num_iso_pack, size;
 870                         if (e == 3) {
 871                                 // Video seems to require isochronous packets scaled with the width;
 872                                 // seemingly six lines is about right, rounded up to the required 1kB
 873                                 // multiple.
 874                                 size = WIDTH * 2 * 6;
 875                                 // Note that for 10-bit input, you'll need to increase size accordingly.
 876                                 //size = size * 4 / 3;
 877                                 if (size % 1024 != 0) {
 878                                         size &= ~1023;
 879                                         size += 1024;
 880                                 }
 881                                 num_iso_pack = (2 << 18) / size;  // 512 kB.
 882                                 printf("Picking %d packets of 0x%x bytes each\n", num_iso_pack, size);
 883                         } else {
 884                                 size = 0xc0;
 885                                 num_iso_pack = 80;
 886                         }
 887                         int num_bytes = num_iso_pack * size;
 888                         uint8_t *buf = new uint8_t[num_bytes];
 889
 890                         xfr = libusb_alloc_transfer(num_iso_pack);
 891                         if (!xfr) {
 892                                 fprintf(stderr, "oom\n");
 893                                 exit(1);
 894                         }
 895
 896                         int ep = LIBUSB_ENDPOINT_IN | e;
 897                         libusb_fill_iso_transfer(xfr, devh, ep, buf, num_bytes,
 898                                 num_iso_pack, cb_xfr, nullptr, 0);
 899                         libusb_set_iso_packet_lengths(xfr, size);
 900                         xfr->user_data = this;
 901                         iso_xfrs.push_back(xfr);
 902                 }
 903         }
 904 }
 905
 906 void BMUSBCapture::start_bm_capture()
 907 {
 908         printf("starting capture\n");
 909         int i = 0;
 910         for (libusb_transfer *xfr : iso_xfrs) {
 911                 printf("submitting transfer...\n");
 912                 int rc = libusb_submit_transfer(xfr);
 913                 ++i;
 914                 if (rc < 0) {
 915                         //printf("num_bytes=%d\n", num_bytes);
 916                         fprintf(stderr, "Error submitting iso to endpoint 0x%02x, number %d: %s\n",
 917                                 xfr->endpoint, i, libusb_error_name(rc));
 918                         exit(1);
 919                 }
 920         }
 921
 922
 923 #if 0
 924         libusb_release_interface(devh, 0);
 925 out:
 926         if (devh)
 927                 libusb_close(devh);
 928         libusb_exit(nullptr);
 929         return rc;
 930 #endif
 931 }
 932
 933 void BMUSBCapture::start_bm_thread()
 934 {
 935         should_quit = false;
 936         usb_thread = thread(&BMUSBCapture::usb_thread_func);
 937 }
 938
 939 void BMUSBCapture::stop_bm_thread()
 940 {
 941         should_quit = true;
 942         usb_thread.join();
 943 }