git.sesse.net Git - nageru/blob - nageru/image_input.cpp

   1 #include "image_input.h"
   2
   3 #include <errno.h>
   4 #include <movit/flat_input.h>
   5 #include <movit/image_format.h>
   6 #include <movit/util.h>
   7 #include <stdint.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11
  12 extern "C" {
  13 #include <libavcodec/avcodec.h>
  14 #include <libavformat/avformat.h>
  15 #include <libavutil/avutil.h>
  16 #include <libavutil/error.h>
  17 #include <libavutil/frame.h>
  18 #include <libavutil/imgutils.h>
  19 #include <libavutil/mem.h>
  20 #include <libavutil/pixfmt.h>
  21 #include <libswscale/swscale.h>
  22 }
  23
  24 #include <epoxy/egl.h>
  25 #include <fcntl.h>
  26 #include <sys/stat.h>
  27 #include <unistd.h>
  28 #include <cstddef>
  29 #include <functional>
  30 #include <mutex>
  31 #include <thread>
  32 #include <utility>
  33 #include <vector>
  34
  35 #include "shared/context.h"
  36 #include "shared/ffmpeg_raii.h"
  37 #include "ffmpeg_util.h"
  38 #include "flags.h"
  39
  40 struct SwsContext;
  41
  42 using namespace std;
  43
  44 ImageInput::ImageInput()
  45         : sRGBSwitchingFlatInput({movit::COLORSPACE_sRGB, movit::GAMMA_sRGB}, movit::FORMAT_RGBA_POSTMULTIPLIED_ALPHA,
  46                                  GL_UNSIGNED_BYTE, 1280, 720)  // Resolution will be overwritten.
  47 {}
  48
  49 ImageInput::ImageInput(const string &filename)
  50         : sRGBSwitchingFlatInput({movit::COLORSPACE_sRGB, movit::GAMMA_sRGB}, movit::FORMAT_RGBA_POSTMULTIPLIED_ALPHA,
  51                                  GL_UNSIGNED_BYTE, 1280, 720),  // Resolution will be overwritten.
  52           pathname(search_for_file_or_die(filename)),
  53           current_image(load_image(filename, pathname))
  54 {
  55         if (current_image == nullptr) {  // Could happen even though search_for_file() returned.
  56                 fprintf(stderr, "Couldn't load image, exiting.\n");
  57                 abort();
  58         }
  59         set_width(current_image->width);
  60         set_height(current_image->height);
  61         set_texture_num(*current_image->tex);
  62 }
  63
  64 void ImageInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
  65 {
  66         // See if the background thread has given us a new version of our image.
  67         // Note: The old version might still be lying around in other ImageInputs
  68         // (in fact, it's likely), but at least the total amount of memory used
  69         // is bounded. Currently we don't even share textures between them,
  70         // so there's a fair amount of OpenGL memory waste anyway (the cache
  71         // is mostly there to save startup time, not RAM).
  72         {
  73                 lock_guard<mutex> lock(all_images_lock);
  74                 assert(all_images.count(pathname));
  75                 if (all_images[pathname] != current_image) {
  76                         current_image = all_images[pathname];
  77                         set_texture_num(*current_image->tex);
  78                 }
  79         }
  80         sRGBSwitchingFlatInput::set_gl_state(glsl_program_num, prefix, sampler_num);
  81 }
  82
  83 shared_ptr<const ImageInput::Image> ImageInput::load_image(const string &filename, const string &pathname)
  84 {
  85         lock_guard<mutex> lock(all_images_lock);  // Held also during loading.
  86         if (all_images.count(pathname)) {
  87                 return all_images[pathname];
  88         }
  89
  90         all_images[pathname] = load_image_raw(pathname);
  91         return all_images[pathname];
  92 }
  93
  94 shared_ptr<const ImageInput::Image> ImageInput::load_image_raw(const string &pathname)
  95 {
  96         // Note: Call before open, not after; otherwise, there's a race.
  97         // (There is now, too, but it tips the correct way. We could use fstat()
  98         // if we had the file descriptor.)
  99         struct stat buf;
 100         if (stat(pathname.c_str(), &buf) != 0) {
 101                 fprintf(stderr, "%s: Error stat-ing file\n", pathname.c_str());
 102                 return nullptr;
 103         }
 104         timespec last_modified = buf.st_mtim;
 105
 106         auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
 107         if (format_ctx == nullptr) {
 108                 fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
 109                 return nullptr;
 110         }
 111
 112         if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
 113                 fprintf(stderr, "%s: Error finding stream info\n", pathname.c_str());
 114                 return nullptr;
 115         }
 116
 117         int stream_index = find_stream_index(format_ctx.get(), AVMEDIA_TYPE_VIDEO);
 118         if (stream_index == -1) {
 119                 fprintf(stderr, "%s: No video stream found\n", pathname.c_str());
 120                 return nullptr;
 121         }
 122
 123         const AVCodecParameters *codecpar = format_ctx->streams[stream_index]->codecpar;
 124         AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr);
 125         if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) {
 126                 fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str());
 127                 return nullptr;
 128         }
 129         const AVCodec *codec = avcodec_find_decoder(codecpar->codec_id);
 130         if (codec == nullptr) {
 131                 fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
 132                 return nullptr;
 133         }
 134         if (avcodec_open2(codec_ctx.get(), codec, nullptr) < 0) {
 135                 fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
 136                 return nullptr;
 137         }
 138         unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
 139                 codec_ctx.get(), avcodec_close);
 140
 141         // Read packets until we have a frame or there are none left.
 142         int frame_finished = 0;
 143         AVFrameWithDeleter frame = av_frame_alloc_unique();
 144         bool eof = false;
 145         do {
 146                 AVPacketWithDeleter pkt = av_packet_alloc_unique();
 147                 pkt->data = nullptr;
 148                 pkt->size = 0;
 149                 if (av_read_frame(format_ctx.get(), pkt.get()) == 0) {
 150                         if (pkt->stream_index != stream_index) {
 151                                 continue;
 152                         }
 153                         if (avcodec_send_packet(codec_ctx.get(), pkt.get()) < 0) {
 154                                 fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str());
 155                                 return nullptr;
 156                         }
 157                 } else {
 158                         eof = true;  // Or error, but ignore that for the time being.
 159                 }
 160
 161                 int err = avcodec_receive_frame(codec_ctx.get(), frame.get());
 162                 if (err == 0) {
 163                         frame_finished = true;
 164                         break;
 165                 } else if (err != AVERROR(EAGAIN)) {
 166                         fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str());
 167                         return nullptr;
 168                 }
 169         } while (!eof);
 170
 171         if (!frame_finished) {
 172                 fprintf(stderr, "%s: Decoder did not output frame.\n", pathname.c_str());
 173                 return nullptr;
 174         }
 175
 176         uint8_t *pic_data[4] = {nullptr};
 177         unique_ptr<uint8_t *, decltype(av_freep)*> pic_data_cleanup(
 178                 &pic_data[0], av_freep);
 179         int linesizes[4];
 180         if (av_image_alloc(pic_data, linesizes, frame->width, frame->height, AV_PIX_FMT_RGBA, 1) < 0) {
 181                 fprintf(stderr, "%s: Could not allocate picture data\n", pathname.c_str());
 182                 return nullptr;
 183         }
 184         unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(
 185                 sws_getContext(frame->width, frame->height,
 186                         (AVPixelFormat)frame->format, frame->width, frame->height,
 187                         AV_PIX_FMT_RGBA, SWS_BICUBIC, nullptr, nullptr, nullptr),
 188                 sws_freeContext);
 189         if (sws_ctx == nullptr) {
 190                 fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
 191                 return nullptr;
 192         }
 193         sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
 194
 195         size_t len = frame->width * frame->height * 4;
 196         unique_ptr<uint8_t[]> image_data(new uint8_t[len]);
 197         av_image_copy_to_buffer(image_data.get(), len, pic_data, linesizes, AV_PIX_FMT_RGBA, frame->width, frame->height, 1);
 198
 199         // Create and upload the texture. We always make mipmaps, since we have
 200         // generally no idea of all the different chains that might crop up.
 201         GLuint tex;
 202         glGenTextures(1, &tex);
 203         check_error();
 204         glBindTexture(GL_TEXTURE_2D, tex);
 205         check_error();
 206         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
 207         check_error();
 208         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 209         check_error();
 210         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 211         check_error();
 212
 213         // Actual upload.
 214         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 215         check_error();
 216         glPixelStorei(GL_UNPACK_ROW_LENGTH, linesizes[0] / 4);
 217         check_error();
 218         glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, frame->width, frame->height, 0, GL_RGBA, GL_UNSIGNED_INT_8_8_8_8_REV, image_data.get());
 219         check_error();
 220         glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
 221         check_error();
 222
 223         glGenerateMipmap(GL_TEXTURE_2D);
 224         check_error();
 225         glBindTexture(GL_TEXTURE_2D, 0);
 226         check_error();
 227
 228         shared_ptr<Image> image(new Image{unsigned(frame->width), unsigned(frame->height), UniqueTexture(new GLuint(tex)), last_modified});
 229         return image;
 230 }
 231
 232 // Fire up a thread to update all images every second.
 233 // We could do inotify, but this is good enough for now.
 234 void ImageInput::update_thread_func(QSurface *surface)
 235 {
 236         pthread_setname_np(pthread_self(), "Update_Images");
 237
 238         eglBindAPI(EGL_OPENGL_API);
 239         QOpenGLContext *context = create_context(surface);
 240         if (!make_current(context, surface)) {
 241                 printf("Couldn't initialize OpenGL context!\n");
 242                 abort();
 243         }
 244
 245         struct stat buf;
 246         for ( ;; ) {
 247                 {
 248                         unique_lock<mutex> lock(update_thread_should_quit_mu);
 249                         update_thread_should_quit_modified.wait_for(lock, chrono::seconds(1), [] { return update_thread_should_quit; });
 250                 }
 251                 if (update_thread_should_quit) {
 252                         return;
 253                 }
 254
 255                 // Go through all loaded images and see if they need to be updated.
 256                 // We do one pass first through the array with no I/O, to avoid
 257                 // blocking the renderer.
 258                 vector<pair<string, timespec>> images_to_check;
 259                 {
 260                         unique_lock<mutex> lock(all_images_lock);
 261                         for (const auto &pathname_and_image : all_images) {
 262                                 const string pathname = pathname_and_image.first;
 263                                 const timespec last_modified = pathname_and_image.second->last_modified;
 264                                 images_to_check.emplace_back(pathname, last_modified);
 265                         }
 266                 }
 267
 268                 for (const auto &pathname_and_timespec : images_to_check) {
 269                         const string pathname = pathname_and_timespec.first;
 270                         const timespec last_modified = pathname_and_timespec.second;
 271
 272                         if (stat(pathname.c_str(), &buf) != 0) {
 273                                 fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", pathname.c_str());
 274                                 continue;
 275                         }
 276                         if (buf.st_mtim.tv_sec == last_modified.tv_sec &&
 277                             buf.st_mtim.tv_nsec == last_modified.tv_nsec) {
 278                                 // Not changed.
 279                                 continue;
 280                         }
 281
 282                         shared_ptr<const Image> image = load_image_raw(pathname);
 283                         if (image == nullptr) {
 284                                 fprintf(stderr, "Couldn't load image, leaving the old in place.\n");
 285                                 continue;
 286                         }
 287
 288                         unique_lock<mutex> lock(all_images_lock);
 289                         all_images[pathname] = image;
 290                 }
 291         }
 292 }
 293
 294 void ImageInput::switch_image(const string &pathname)
 295 {
 296 #ifndef NDEBUG
 297         lock_guard<mutex> lock(all_images_lock);
 298         assert(all_images.count(pathname));
 299 #endif
 300         this->pathname = pathname;
 301 }
 302
 303 void ImageInput::start_update_thread(QSurface *surface)
 304 {
 305         update_thread = thread(update_thread_func, surface);
 306 }
 307
 308 void ImageInput::end_update_thread()
 309
 310 {
 311         {
 312                 lock_guard<mutex> lock(update_thread_should_quit_mu);
 313                 update_thread_should_quit = true;
 314                 update_thread_should_quit_modified.notify_all();
 315         }
 316         update_thread.join();
 317 }
 318
 319 mutex ImageInput::all_images_lock;
 320 map<string, shared_ptr<const ImageInput::Image>> ImageInput::all_images;
 321 thread ImageInput::update_thread;
 322 mutex ImageInput::update_thread_should_quit_mu;
 323 bool ImageInput::update_thread_should_quit = false;
 324 condition_variable ImageInput::update_thread_should_quit_modified;