1 #include "image_input.h"
3 #include <movit/image_format.h>
6 #include <libavcodec/avcodec.h>
7 #include <libavformat/avformat.h>
8 #include <libavutil/imgutils.h>
9 #include <libavutil/pixfmt.h>
10 #include <libswscale/swscale.h>
13 #include <sys/types.h>
27 string search_for_file(const string &filename)
29 // Look for the file in all theme_dirs until we find one;
30 // that will be the permanent resolution of this file, whether
31 // it is actually valid or not.
32 // We store errors from all the attempts, and show them
33 // once we know we can't find any of them.
34 vector<string> errors;
35 for (const string &dir : global_flags.theme_dirs) {
36 string pathname = dir + "/" + filename;
37 if (access(pathname.c_str(), O_RDONLY) == 0) {
41 snprintf(buf, sizeof(buf), "%s: %s", pathname.c_str(), strerror(errno));
42 errors.push_back(buf);
46 for (const string &error : errors) {
47 fprintf(stderr, "%s\n", error.c_str());
49 fprintf(stderr, "Couldn't find %s in any directory in --theme-dirs, exiting.\n",
56 ImageInput::ImageInput(const string &filename)
57 : movit::FlatInput({movit::COLORSPACE_sRGB, movit::GAMMA_sRGB}, movit::FORMAT_RGBA_POSTMULTIPLIED_ALPHA,
58 GL_UNSIGNED_BYTE, 1280, 720), // FIXME
59 pathname(search_for_file(filename)),
60 current_image(load_image(pathname))
62 if (current_image == nullptr) { // Could happen even though search_for_file() returned.
63 fprintf(stderr, "Couldn't load image, exiting.\n");
66 set_pixel_data(current_image->pixels.get());
69 void ImageInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
71 // See if the background thread has given us a new version of our image.
72 // Note: The old version might still be lying around in other ImageInputs
73 // (in fact, it's likely), but at least the total amount of memory used
74 // is bounded. Currently we don't even share textures between them,
75 // so there's a fair amount of OpenGL memory waste anyway (the cache
76 // is mostly there to save startup time, not RAM).
78 unique_lock<mutex> lock(all_images_lock);
79 if (all_images[pathname] != current_image) {
80 current_image = all_images[pathname];
81 set_pixel_data(current_image->pixels.get());
84 movit::FlatInput::set_gl_state(glsl_program_num, prefix, sampler_num);
87 shared_ptr<const ImageInput::Image> ImageInput::load_image(const string &pathname)
89 unique_lock<mutex> lock(all_images_lock); // Held also during loading.
90 if (all_images.count(pathname)) {
91 return all_images[pathname];
94 all_images[pathname] = load_image_raw(pathname);
95 timespec first_modified = all_images[pathname]->last_modified;
96 update_threads[pathname] =
97 thread(bind(update_thread_func, pathname, first_modified));
99 return all_images[pathname];
102 // Some helpers to make RAII versions of FFmpeg objects.
103 // The cleanup functions don't interact all that well with unique_ptr,
104 // so things get a bit messy and verbose, but overall it's worth it to ensure
105 // we never leak things by accident in error paths.
109 void avformat_close_input_unique(AVFormatContext *format_ctx)
111 avformat_close_input(&format_ctx);
114 unique_ptr<AVFormatContext, decltype(avformat_close_input_unique)*>
115 avformat_open_input_unique(const char *pathname,
116 AVInputFormat *fmt, AVDictionary **options)
118 AVFormatContext *format_ctx = nullptr;
119 if (avformat_open_input(&format_ctx, pathname, fmt, options) != 0) {
120 format_ctx = nullptr;
122 return unique_ptr<AVFormatContext, decltype(avformat_close_input_unique)*>(
123 format_ctx, avformat_close_input_unique);
126 void av_frame_free_unique(AVFrame *frame)
128 av_frame_free(&frame);
131 unique_ptr<AVFrame, decltype(av_frame_free_unique)*>
132 av_frame_alloc_unique()
134 AVFrame *frame = av_frame_alloc();
135 return unique_ptr<AVFrame, decltype(av_frame_free_unique)*>(
136 frame, av_frame_free_unique);
141 shared_ptr<const ImageInput::Image> ImageInput::load_image_raw(const string &pathname)
143 // Note: Call before open, not after; otherwise, there's a race.
144 // (There is now, too, but it tips the correct way. We could use fstat()
145 // if we had the file descriptor.)
147 if (stat(pathname.c_str(), &buf) != 0) {
148 fprintf(stderr, "%s: Error stat-ing file\n", pathname.c_str());
151 timespec last_modified = buf.st_mtim;
153 auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
154 if (format_ctx == nullptr) {
155 fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
159 if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
160 fprintf(stderr, "%s: Error finding stream info\n", pathname.c_str());
164 int stream_index = -1;
165 for (unsigned i = 0; i < format_ctx->nb_streams; ++i) {
166 if (format_ctx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
171 if (stream_index == -1) {
172 fprintf(stderr, "%s: No video stream found\n", pathname.c_str());
176 AVCodecContext *codec_ctx = format_ctx->streams[stream_index]->codec;
177 AVCodec *codec = avcodec_find_decoder(codec_ctx->codec_id);
178 if (codec == nullptr) {
179 fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
182 if (avcodec_open2(codec_ctx, codec, nullptr) < 0) {
183 fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
186 unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
187 codec_ctx, avcodec_close);
189 // Read packets until we have a frame or there are none left.
190 int frame_finished = 0;
191 auto frame = av_frame_alloc_unique();
194 unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
195 &pkt, av_packet_unref);
196 av_init_packet(&pkt);
199 if (av_read_frame(format_ctx.get(), &pkt) < 0) {
202 if (pkt.stream_index != stream_index) {
206 if (avcodec_decode_video2(codec_ctx, frame.get(), &frame_finished, &pkt) < 0) {
207 fprintf(stderr, "%s: Cannot decode frame\n", pathname.c_str());
210 } while (!frame_finished);
212 // See if there's a cached frame for us.
213 if (!frame_finished) {
217 if (avcodec_decode_video2(codec_ctx, frame.get(), &frame_finished, &pkt) < 0) {
218 fprintf(stderr, "%s: Cannot decode frame\n", pathname.c_str());
222 if (!frame_finished) {
223 fprintf(stderr, "%s: Decoder did not output frame.\n", pathname.c_str());
227 // TODO: Scale down if needed!
228 uint8_t *pic_data[4] = {nullptr};
229 unique_ptr<uint8_t *, decltype(av_freep)*> pic_data_cleanup(
230 &pic_data[0], av_freep);
232 if (av_image_alloc(pic_data, linesizes, frame->width, frame->height, AV_PIX_FMT_RGBA, 1) < 0) {
233 fprintf(stderr, "%s: Could not allocate picture data\n", pathname.c_str());
236 unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(
237 sws_getContext(frame->width, frame->height,
238 (AVPixelFormat)frame->format, frame->width, frame->height,
239 AV_PIX_FMT_RGBA, SWS_BICUBIC, nullptr, nullptr, nullptr),
241 if (sws_ctx == nullptr) {
242 fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
245 sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
247 size_t len = frame->width * frame->height * 4;
248 unique_ptr<uint8_t[]> image_data(new uint8_t[len]);
249 av_image_copy_to_buffer(image_data.get(), len, pic_data, linesizes, AV_PIX_FMT_RGBA, frame->width, frame->height, 1);
251 shared_ptr<Image> image(new Image{move(image_data), last_modified});
255 // Fire up a thread to update the image every second.
256 // We could do inotify, but this is good enough for now.
257 void ImageInput::update_thread_func(const std::string &pathname, const timespec &first_modified)
259 timespec last_modified = first_modified;
264 if (threads_should_quit) {
268 if (stat(pathname.c_str(), &buf) != 0) {
269 fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", pathname.c_str());
272 if (buf.st_mtim.tv_sec == last_modified.tv_sec &&
273 buf.st_mtim.tv_nsec == last_modified.tv_nsec) {
277 shared_ptr<const Image> image = load_image_raw(pathname);
278 if (image == nullptr) {
279 fprintf(stderr, "Couldn't load image, leaving the old in place.\n");
282 fprintf(stderr, "Loaded new version of %s from disk.\n", pathname.c_str());
283 unique_lock<mutex> lock(all_images_lock);
284 all_images[pathname] = image;
285 last_modified = image->last_modified;
289 void ImageInput::shutdown_updaters()
291 // TODO: Kick these out of the sleep before one second?
292 threads_should_quit = true;
294 for (auto &it : update_threads) {
299 mutex ImageInput::all_images_lock;
300 map<string, shared_ptr<const ImageInput::Image>> ImageInput::all_images;
301 map<string, thread> ImageInput::update_threads;
302 volatile bool ImageInput::threads_should_quit = false;