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