#include <libswscale/swscale.h>
}
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <mutex>
+#include <thread>
+
using namespace std;
-ImageInput::ImageInput(const std::string &filename)
+ImageInput::ImageInput(const string &filename)
: movit::FlatInput({movit::COLORSPACE_sRGB, movit::GAMMA_sRGB}, movit::FORMAT_RGBA_POSTMULTIPLIED_ALPHA,
- GL_UNSIGNED_BYTE, 1280, 720) // FIXME
+ GL_UNSIGNED_BYTE, 1280, 720), // FIXME
+ filename(filename),
+ current_image(load_image(filename))
+{
+ if (current_image == nullptr) {
+ fprintf(stderr, "Couldn't load image, exiting.\n");
+ exit(1);
+ }
+ set_pixel_data(current_image->pixels.get());
+}
+
+void ImageInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
+{
+ // See if the background thread has given us a new version of our image.
+ // Note: The old version might still be lying around in other ImageInputs
+ // (in fact, it's likely), but at least the total amount of memory used
+ // is bounded. Currently we don't even share textures between them,
+ // so there's a fair amount of OpenGL memory waste anyway (the cache
+ // is mostly there to save startup time, not RAM).
+ {
+ unique_lock<mutex> lock(all_images_lock);
+ if (all_images[filename] != current_image) {
+ current_image = all_images[filename];
+ set_pixel_data(current_image->pixels.get());
+ }
+ }
+ movit::FlatInput::set_gl_state(glsl_program_num, prefix, sampler_num);
+}
+
+shared_ptr<const ImageInput::Image> ImageInput::load_image(const string &filename)
+{
+ unique_lock<mutex> lock(all_images_lock); // Held also during loading.
+ if (all_images.count(filename)) {
+ return all_images[filename];
+ }
+
+ all_images[filename] = load_image_raw(filename);
+ timespec first_modified = all_images[filename]->last_modified;
+ update_threads[filename] =
+ thread(bind(update_thread_func, filename, first_modified));
+
+ return all_images[filename];
+}
+
+// Some helpers to make RAII versions of FFmpeg objects.
+// The cleanup functions don't interact all that well with unique_ptr,
+// so things get a bit messy and verbose, but overall it's worth it to ensure
+// we never leak things by accident in error paths.
+
+namespace {
+
+void avformat_close_input_unique(AVFormatContext *format_ctx)
+{
+ avformat_close_input(&format_ctx);
+}
+
+unique_ptr<AVFormatContext, decltype(avformat_close_input_unique)*>
+avformat_open_input_unique(const char *filename,
+ AVInputFormat *fmt, AVDictionary **options)
{
AVFormatContext *format_ctx = nullptr;
- if (avformat_open_input(&format_ctx, filename.c_str(), nullptr, nullptr) != 0) {
+ if (avformat_open_input(&format_ctx, filename, fmt, options) != 0) {
+ format_ctx = nullptr;
+ }
+ return unique_ptr<AVFormatContext, decltype(avformat_close_input_unique)*>(
+ format_ctx, avformat_close_input_unique);
+}
+
+void av_frame_free_unique(AVFrame *frame)
+{
+ av_frame_free(&frame);
+}
+
+unique_ptr<AVFrame, decltype(av_frame_free_unique)*>
+av_frame_alloc_unique()
+{
+ AVFrame *frame = av_frame_alloc();
+ return unique_ptr<AVFrame, decltype(av_frame_free_unique)*>(
+ frame, av_frame_free_unique);
+}
+
+} // namespace
+
+shared_ptr<const ImageInput::Image> ImageInput::load_image_raw(const string &filename)
+{
+ // Note: Call before open, not after; otherwise, there's a race.
+ // (There is now, too, but it tips the correct way. We could use fstat()
+ // if we had the file descriptor.)
+ struct stat buf;
+ if (stat(filename.c_str(), &buf) != 0) {
+ fprintf(stderr, "%s: Error stat-ing file\n", filename.c_str());
+ return nullptr;
+ }
+ timespec last_modified = buf.st_mtim;
+
+ auto format_ctx = avformat_open_input_unique(filename.c_str(), nullptr, nullptr);
+ if (format_ctx == nullptr) {
fprintf(stderr, "%s: Error opening file\n", filename.c_str());
- exit(1);
+ return nullptr;
}
- if (avformat_find_stream_info(format_ctx, nullptr) < 0) {
+ if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
fprintf(stderr, "%s: Error finding stream info\n", filename.c_str());
- exit(1);
+ return nullptr;
}
int stream_index = -1;
}
if (stream_index == -1) {
fprintf(stderr, "%s: No video stream found\n", filename.c_str());
- exit(1);
+ return nullptr;
}
AVCodecContext *codec_ctx = format_ctx->streams[stream_index]->codec;
AVCodec *codec = avcodec_find_decoder(codec_ctx->codec_id);
if (codec == nullptr) {
fprintf(stderr, "%s: Cannot find decoder\n", filename.c_str());
- exit(1);
+ return nullptr;
}
if (avcodec_open2(codec_ctx, codec, nullptr) < 0) {
fprintf(stderr, "%s: Cannot open decoder\n", filename.c_str());
- exit(1);
+ return nullptr;
}
+ unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
+ codec_ctx, avcodec_close);
- // Read packets until we have a frame.
+ // Read packets until we have a frame or there are none left.
int frame_finished = 0;
- AVFrame *frame = av_frame_alloc();
+ auto frame = av_frame_alloc_unique();
do {
AVPacket pkt;
+ unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
+ &pkt, av_packet_unref);
av_init_packet(&pkt);
pkt.data = nullptr;
pkt.size = 0;
- if (av_read_frame(format_ctx, &pkt) < 0) {
- fprintf(stderr, "%s: Cannot read frame\n", filename.c_str());
- exit(1);
+ if (av_read_frame(format_ctx.get(), &pkt) < 0) {
+ break;
}
if (pkt.stream_index != stream_index) {
- av_free_packet(&pkt);
continue;
}
- if (avcodec_decode_video2(codec_ctx, frame, &frame_finished, &pkt) < 0) {
+ if (avcodec_decode_video2(codec_ctx, frame.get(), &frame_finished, &pkt) < 0) {
fprintf(stderr, "%s: Cannot decode frame\n", filename.c_str());
- exit(1);
+ return nullptr;
}
- av_free_packet(&pkt);
} while (!frame_finished);
+ // See if there's a cached frame for us.
+ if (!frame_finished) {
+ AVPacket pkt;
+ pkt.data = nullptr;
+ pkt.size = 0;
+ if (avcodec_decode_video2(codec_ctx, frame.get(), &frame_finished, &pkt) < 0) {
+ fprintf(stderr, "%s: Cannot decode frame\n", filename.c_str());
+ return nullptr;
+ }
+ }
+ if (!frame_finished) {
+ fprintf(stderr, "%s: Decoder did not output frame.\n", filename.c_str());
+ return nullptr;
+ }
+
// TODO: Scale down if needed!
- AVPicture pic;
- avpicture_alloc(&pic, PIX_FMT_RGBA, frame->width, frame->height);
- SwsContext *sws_ctx = sws_getContext(frame->width, frame->height,
- (PixelFormat)frame->format, frame->width, frame->height,
- PIX_FMT_RGBA, SWS_BICUBIC, nullptr, nullptr, nullptr);
+ uint8_t *pic_data[4] = {nullptr};
+ unique_ptr<uint8_t *, decltype(av_freep)*> pic_data_cleanup(
+ &pic_data[0], av_freep);
+ int linesizes[4];
+ if (av_image_alloc(pic_data, linesizes, frame->width, frame->height, AV_PIX_FMT_RGBA, 1) < 0) {
+ fprintf(stderr, "%s: Could not allocate picture data\n", filename.c_str());
+ return nullptr;
+ }
+ unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(
+ sws_getContext(frame->width, frame->height,
+ (AVPixelFormat)frame->format, frame->width, frame->height,
+ AV_PIX_FMT_RGBA, SWS_BICUBIC, nullptr, nullptr, nullptr),
+ sws_freeContext);
if (sws_ctx == nullptr) {
fprintf(stderr, "%s: Could not create scaler context\n", filename.c_str());
- exit(1);
+ return nullptr;
}
- sws_scale(sws_ctx, frame->data, frame->linesize, 0, frame->height, pic.data, pic.linesize);
- sws_freeContext(sws_ctx);
+ sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
size_t len = frame->width * frame->height * 4;
- image_data.reset(new uint8_t[len]);
- av_image_copy_to_buffer(image_data.get(), len, pic.data, pic.linesize, PIX_FMT_RGBA, frame->width, frame->height, 1);
- set_pixel_data(image_data.get());
+ unique_ptr<uint8_t[]> image_data(new uint8_t[len]);
+ av_image_copy_to_buffer(image_data.get(), len, pic_data, linesizes, AV_PIX_FMT_RGBA, frame->width, frame->height, 1);
- avpicture_free(&pic);
- av_frame_free(&frame);
- avcodec_close(codec_ctx);
- avformat_close_input(&format_ctx);
+ shared_ptr<Image> image(new Image{move(image_data), last_modified});
+ return image;
}
+
+// Fire up a thread to update the image every second.
+// We could do inotify, but this is good enough for now.
+void ImageInput::update_thread_func(const std::string &filename, const timespec &first_modified)
+{
+ timespec last_modified = first_modified;
+ struct stat buf;
+ for ( ;; ) {
+ sleep(1);
+
+ if (threads_should_quit) {
+ return;
+ }
+
+ if (stat(filename.c_str(), &buf) != 0) {
+ fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", filename.c_str());
+ continue;
+ }
+ if (buf.st_mtim.tv_sec == last_modified.tv_sec &&
+ buf.st_mtim.tv_nsec == last_modified.tv_nsec) {
+ // Not changed.
+ continue;
+ }
+ shared_ptr<const Image> image = load_image_raw(filename);
+ if (image == nullptr) {
+ fprintf(stderr, "Couldn't load image, leaving the old in place.\n");
+ continue;
+ }
+ fprintf(stderr, "Loaded new version of %s from disk.\n", filename.c_str());
+ unique_lock<mutex> lock(all_images_lock);
+ all_images[filename] = image;
+ last_modified = image->last_modified;
+ }
+}
+
+void ImageInput::shutdown_updaters()
+{
+ // TODO: Kick these out of the sleep before one second?
+ threads_should_quit = true;
+
+ for (auto &it : update_threads) {
+ it.second.join();
+ }
+}
+
+mutex ImageInput::all_images_lock;
+map<string, shared_ptr<const ImageInput::Image>> ImageInput::all_images;
+map<string, thread> ImageInput::update_threads;
+volatile bool ImageInput::threads_should_quit = false;
projects / nageru / blobdiff