#include "image_input.h"
+#include <errno.h>
+#include <movit/flat_input.h>
#include <movit/image_format.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
extern "C" {
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
+#include <libavutil/avutil.h>
+#include <libavutil/error.h>
+#include <libavutil/frame.h>
#include <libavutil/imgutils.h>
+#include <libavutil/mem.h>
#include <libavutil/pixfmt.h>
#include <libswscale/swscale.h>
}
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <cstddef>
+#include <functional>
+#include <mutex>
+#include <thread>
+#include <utility>
+#include <vector>
+
+#include "ffmpeg_raii.h"
+#include "ffmpeg_util.h"
+#include "flags.h"
+
+struct SwsContext;
+
using namespace std;
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), // Resolution will be overwritten.
+ filename(filename),
+ pathname(search_for_file_or_die(filename)),
+ current_image(load_image(filename, pathname))
{
- const uint8_t *pixel_data = load_image(filename);
- if (pixel_data == nullptr) {
+ if (current_image == nullptr) { // Could happen even though search_for_file() returned.
fprintf(stderr, "Couldn't load image, exiting.\n");
exit(1);
}
- set_pixel_data(pixel_data);
+ set_width(current_image->width);
+ set_height(current_image->height);
+ set_pixel_data(current_image->pixels.get());
}
-// 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)
+void ImageInput::set_gl_state(GLuint glsl_program_num, const string& prefix, unsigned *sampler_num)
{
- avformat_close_input(&format_ctx);
+ // 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[pathname] != current_image) {
+ current_image = all_images[pathname];
+ set_pixel_data(current_image->pixels.get());
+ }
+ }
+ movit::FlatInput::set_gl_state(glsl_program_num, prefix, sampler_num);
}
-unique_ptr<AVFormatContext, decltype(avformat_close_input_unique)*>
-avformat_open_input_unique(const char *filename,
- AVInputFormat *fmt, AVDictionary **options)
+shared_ptr<const ImageInput::Image> ImageInput::load_image(const string &filename, const string &pathname)
{
- AVFormatContext *format_ctx = nullptr;
- if (avformat_open_input(&format_ctx, filename, fmt, options) != 0) {
- format_ctx = nullptr;
+ unique_lock<mutex> lock(all_images_lock); // Held also during loading.
+ if (all_images.count(pathname)) {
+ return all_images[pathname];
}
- 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);
-}
+ all_images[pathname] = load_image_raw(pathname);
+ timespec first_modified = all_images[pathname]->last_modified;
+ update_threads[pathname] =
+ thread(bind(update_thread_func, filename, pathname, first_modified));
-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);
+ return all_images[pathname];
}
-} // namespace
-
-const uint8_t *ImageInput::load_image(const string &filename)
+shared_ptr<const ImageInput::Image> ImageInput::load_image_raw(const string &pathname)
{
- if (all_images.count(filename)) {
- return all_images[filename].get();
+ // 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(pathname.c_str(), &buf) != 0) {
+ fprintf(stderr, "%s: Error stat-ing file\n", pathname.c_str());
+ return nullptr;
}
+ timespec last_modified = buf.st_mtim;
- auto format_ctx = avformat_open_input_unique(filename.c_str(), nullptr, nullptr);
+ auto format_ctx = avformat_open_input_unique(pathname.c_str(), nullptr, nullptr);
if (format_ctx == nullptr) {
- fprintf(stderr, "%s: Error opening file\n", filename.c_str());
+ fprintf(stderr, "%s: Error opening file\n", pathname.c_str());
return nullptr;
}
if (avformat_find_stream_info(format_ctx.get(), nullptr) < 0) {
- fprintf(stderr, "%s: Error finding stream info\n", filename.c_str());
+ fprintf(stderr, "%s: Error finding stream info\n", pathname.c_str());
return nullptr;
}
- int stream_index = -1;
- for (unsigned i = 0; i < format_ctx->nb_streams; ++i) {
- if (format_ctx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
- stream_index = i;
- break;
- }
- }
+ int stream_index = find_stream_index(format_ctx.get(), AVMEDIA_TYPE_VIDEO);
if (stream_index == -1) {
- fprintf(stderr, "%s: No video stream found\n", filename.c_str());
+ fprintf(stderr, "%s: No video stream found\n", pathname.c_str());
return nullptr;
}
- AVCodecContext *codec_ctx = format_ctx->streams[stream_index]->codec;
- AVCodec *codec = avcodec_find_decoder(codec_ctx->codec_id);
+ const AVCodecParameters *codecpar = format_ctx->streams[stream_index]->codecpar;
+ AVCodecContextWithDeleter codec_ctx = avcodec_alloc_context3_unique(nullptr);
+ if (avcodec_parameters_to_context(codec_ctx.get(), codecpar) < 0) {
+ fprintf(stderr, "%s: Cannot fill codec parameters\n", pathname.c_str());
+ return nullptr;
+ }
+ AVCodec *codec = avcodec_find_decoder(codecpar->codec_id);
if (codec == nullptr) {
- fprintf(stderr, "%s: Cannot find decoder\n", filename.c_str());
+ fprintf(stderr, "%s: Cannot find decoder\n", pathname.c_str());
return nullptr;
}
- if (avcodec_open2(codec_ctx, codec, nullptr) < 0) {
- fprintf(stderr, "%s: Cannot open decoder\n", filename.c_str());
+ if (avcodec_open2(codec_ctx.get(), codec, nullptr) < 0) {
+ fprintf(stderr, "%s: Cannot open decoder\n", pathname.c_str());
return nullptr;
}
unique_ptr<AVCodecContext, decltype(avcodec_close)*> codec_ctx_cleanup(
- codec_ctx, avcodec_close);
+ codec_ctx.get(), 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;
- auto frame = av_frame_alloc_unique();
+ AVFrameWithDeleter frame = av_frame_alloc_unique();
+ bool eof = false;
do {
AVPacket pkt;
unique_ptr<AVPacket, decltype(av_packet_unref)*> pkt_cleanup(
av_init_packet(&pkt);
pkt.data = nullptr;
pkt.size = 0;
- if (av_read_frame(format_ctx.get(), &pkt) < 0) {
- fprintf(stderr, "%s: Cannot read frame\n", filename.c_str());
- return nullptr;
- }
- if (pkt.stream_index != stream_index) {
- continue;
+ if (av_read_frame(format_ctx.get(), &pkt) == 0) {
+ if (pkt.stream_index != stream_index) {
+ continue;
+ }
+ if (avcodec_send_packet(codec_ctx.get(), &pkt) < 0) {
+ fprintf(stderr, "%s: Cannot send packet to codec.\n", pathname.c_str());
+ return nullptr;
+ }
+ } else {
+ eof = true; // Or error, but ignore that for the time being.
}
- if (avcodec_decode_video2(codec_ctx, frame.get(), &frame_finished, &pkt) < 0) {
- fprintf(stderr, "%s: Cannot decode frame\n", filename.c_str());
+ int err = avcodec_receive_frame(codec_ctx.get(), frame.get());
+ if (err == 0) {
+ frame_finished = true;
+ break;
+ } else if (err != AVERROR(EAGAIN)) {
+ fprintf(stderr, "%s: Cannot receive frame from codec.\n", pathname.c_str());
return nullptr;
}
- } while (!frame_finished);
+ } while (!eof);
+
+ if (!frame_finished) {
+ fprintf(stderr, "%s: Decoder did not output frame.\n", pathname.c_str());
+ return nullptr;
+ }
- // TODO: Scale down if needed!
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());
+ fprintf(stderr, "%s: Could not allocate picture data\n", pathname.c_str());
return nullptr;
}
unique_ptr<SwsContext, decltype(sws_freeContext)*> sws_ctx(
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());
+ fprintf(stderr, "%s: Could not create scaler context\n", pathname.c_str());
return nullptr;
}
sws_scale(sws_ctx.get(), frame->data, frame->linesize, 0, frame->height, pic_data, linesizes);
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);
- all_images[filename] = move(image_data);
- return all_images[filename].get();
+ shared_ptr<Image> image(new Image{unsigned(frame->width), unsigned(frame->height), 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 std::string &pathname, const timespec &first_modified)
+{
+ char thread_name[16];
+ snprintf(thread_name, sizeof(thread_name), "Update_%s", filename.c_str());
+ pthread_setname_np(pthread_self(), thread_name);
+
+ timespec last_modified = first_modified;
+ struct stat buf;
+ for ( ;; ) {
+ {
+ unique_lock<mutex> lock(threads_should_quit_mu);
+ threads_should_quit_modified.wait_for(lock, chrono::seconds(1), []() { return threads_should_quit; });
+ }
+
+ if (threads_should_quit) {
+ return;
+ }
+
+ if (stat(pathname.c_str(), &buf) != 0) {
+ fprintf(stderr, "%s: Couldn't check for new version, leaving the old in place.\n", pathname.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(pathname);
+ 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", pathname.c_str());
+ unique_lock<mutex> lock(all_images_lock);
+ all_images[pathname] = image;
+ last_modified = image->last_modified;
+ }
+}
+
+void ImageInput::shutdown_updaters()
+{
+ {
+ unique_lock<mutex> lock(threads_should_quit_mu);
+ threads_should_quit = true;
+ threads_should_quit_modified.notify_all();
+ }
+ for (auto &it : update_threads) {
+ it.second.join();
+ }
}
-map<string, unique_ptr<uint8_t[]>> ImageInput::all_images;
+mutex ImageInput::all_images_lock;
+map<string, shared_ptr<const ImageInput::Image>> ImageInput::all_images;
+map<string, thread> ImageInput::update_threads;
+mutex ImageInput::threads_should_quit_mu;
+bool ImageInput::threads_should_quit = false;
+condition_variable ImageInput::threads_should_quit_modified;