#include "defs.h"
#include "jpeg_destroyer.h"
+#include "jpeglib_error_wrapper.h"
#include "shared/post_to_main_thread.h"
#include "video_stream.h"
#include "ycbcr_converter.h"
frame.reset(new Frame);
jpeg_decompress_struct dinfo;
- jpeg_error_mgr jerr;
- dinfo.err = jpeg_std_error(&jerr);
- jpeg_create_decompress(&dinfo);
+ JPEGWrapErrorManager error_mgr(&dinfo);
+ if (!error_mgr.run([&dinfo]{ jpeg_create_decompress(&dinfo); })) {
+ return get_black_frame();
+ }
JPEGDestroyer destroy_dinfo(&dinfo);
- jpeg_mem_src(&dinfo, reinterpret_cast<const unsigned char *>(jpeg.data()), jpeg.size());
- jpeg_read_header(&dinfo, true);
+ if (!error_mgr.run([&dinfo, &jpeg]{
+ jpeg_mem_src(&dinfo, reinterpret_cast<const unsigned char *>(jpeg.data()), jpeg.size());
+ jpeg_read_header(&dinfo, true);
+ })) {
+ return get_black_frame();
+ }
if (dinfo.num_components != 3) {
fprintf(stderr, "Not a color JPEG. (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",
dinfo.comp_info[0].h_samp_factor, dinfo.comp_info[0].v_samp_factor,
dinfo.comp_info[1].h_samp_factor, dinfo.comp_info[1].v_samp_factor,
dinfo.comp_info[2].h_samp_factor, dinfo.comp_info[2].v_samp_factor);
- exit(1);
+ return get_black_frame();
}
if (dinfo.comp_info[0].h_samp_factor != dinfo.max_h_samp_factor ||
dinfo.comp_info[0].v_samp_factor != dinfo.max_v_samp_factor || // Y' must not be subsampled.
}
dinfo.raw_data_out = true;
- jpeg_start_decompress(&dinfo);
+ if (!error_mgr.run([&dinfo]{
+ jpeg_start_decompress(&dinfo);
+ })) {
+ return get_black_frame();
+ }
frame->width = dinfo.output_width;
frame->height = dinfo.output_height;
frame->pitch_y = luma_width_blocks * DCTSIZE;
frame->pitch_chroma = chroma_width_blocks * DCTSIZE;
- JSAMPROW yptr[v_mcu_size], cbptr[v_mcu_size], crptr[v_mcu_size];
- JSAMPARRAY data[3] = { yptr, cbptr, crptr };
- for (unsigned y = 0; y < mcu_height_blocks; ++y) {
- // NOTE: The last elements of cbptr/crptr will be unused for vertically subsampled chroma.
- for (unsigned yy = 0; yy < v_mcu_size; ++yy) {
- yptr[yy] = frame->y.get() + (y * DCTSIZE * dinfo.max_v_samp_factor + yy) * frame->pitch_y;
- cbptr[yy] = frame->cb.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
- crptr[yy] = frame->cr.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
+ if (!error_mgr.run([&dinfo, &frame, v_mcu_size, mcu_height_blocks] {
+ JSAMPROW yptr[v_mcu_size], cbptr[v_mcu_size], crptr[v_mcu_size];
+ JSAMPARRAY data[3] = { yptr, cbptr, crptr };
+ for (unsigned y = 0; y < mcu_height_blocks; ++y) {
+ // NOTE: The last elements of cbptr/crptr will be unused for vertically subsampled chroma.
+ for (unsigned yy = 0; yy < v_mcu_size; ++yy) {
+ yptr[yy] = frame->y.get() + (y * DCTSIZE * dinfo.max_v_samp_factor + yy) * frame->pitch_y;
+ cbptr[yy] = frame->cb.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
+ crptr[yy] = frame->cr.get() + (y * DCTSIZE * dinfo.comp_info[1].v_samp_factor + yy) * frame->pitch_chroma;
+ }
+
+ jpeg_read_raw_data(&dinfo, data, v_mcu_size);
}
- jpeg_read_raw_data(&dinfo, data, v_mcu_size);
+ (void)jpeg_finish_decompress(&dinfo);
+ })) {
+ return get_black_frame();
}
- (void)jpeg_finish_decompress(&dinfo);
-
return frame;
}
// Don't refresh immediately; we might not have an OpenGL context here.
overlay_input_needs_refresh = true;
}
+
+shared_ptr<Frame> get_black_frame()
+{
+ static shared_ptr<Frame> black_frame;
+ static once_flag flag;
+ call_once(flag, [] {
+ black_frame.reset(new Frame);
+ black_frame->y.reset(new uint8_t[1280 * 720]);
+ black_frame->cb.reset(new uint8_t[(1280 / 2) * (720 / 2)]);
+ black_frame->cr.reset(new uint8_t[(1280 / 2) * (720 / 2)]);
+ black_frame->width = 1280;
+ black_frame->height = 720;
+ black_frame->chroma_subsampling_x = 2;
+ black_frame->chroma_subsampling_y = 2;
+ black_frame->pitch_y = 1280;
+ black_frame->pitch_chroma = 1280 / 2;
+ });
+ return black_frame;
+}
--- /dev/null
+#ifndef _JPEGLIB_ERROR_WRAPPER
+#define _JPEGLIB_ERROR_WRAPPER 1
+
+/*
+ A wrapper class for libjpeg's very cumbersome error handling.
+ By default, any error will simply exit(); you can set your own
+ error handler, but it can't return. You can't throw exceptions
+ through C code legally, so the only real choice is setjmp/longjmp,
+ which is also what libjpeg recommends. However, longjmp has
+ undefined behavior if a similar try/catch pair would invoke
+ running any nontrivial destructors, so it's better to wrap it
+ into a common class where we know for sure there are no such
+ destructors; we choose to simply convert it into a normal
+ true/false idiom for success/failure.
+
+ Use as:
+
+ JPEGWrapErrorManager error_mgr(&cinfo);
+ if (!error_mgr.run([&cinfo]{ jpeg_read_header(&cinfo, true); })) {
+ // Something went wrong.
+ return nullptr;
+ }
+ if (!error_mgr.run([&cinfo]{ jpeg_start_decompress(&cinfo); })) {
+ // Something went wrong.
+ return nullptr;
+ }
+ // etc.
+
+ If you call libjpeg calls outside of run() and they fail, or if
+ you declare objects with nontrivial destructors in your lambda
+ (including in the capture), you end up in undefined behavior.
+ */
+
+#include <jpeglib.h>
+#include <setjmp.h>
+
+struct JPEGWrapErrorManager {
+ struct jpeg_error_mgr pub;
+ jmp_buf setjmp_buffer;
+
+ explicit JPEGWrapErrorManager(jpeg_compress_struct *cinfo) // Does not take ownership.
+ {
+ cinfo->err = jpeg_std_error(&pub);
+ pub.error_exit = error_exit_thunk;
+ }
+
+ explicit JPEGWrapErrorManager(jpeg_decompress_struct *dinfo) // Does not take ownership.
+ {
+ dinfo->err = jpeg_std_error(&pub);
+ pub.error_exit = error_exit_thunk;
+ }
+
+ static void error_exit_thunk(jpeg_common_struct *cinfo)
+ {
+ ((JPEGWrapErrorManager *)cinfo->err)->error_exit(cinfo);
+ }
+
+ void error_exit(jpeg_common_struct *cinfo)
+ {
+ (pub.output_message)(cinfo);
+ longjmp(setjmp_buffer, 1);
+ }
+
+ // Returns false if and only if the call failed.
+ template<class T>
+ inline bool run(T &&func)
+ {
+ if (setjmp(setjmp_buffer)) {
+ return false;
+ }
+ func();
+ return true;
+ }
+};
+
+#endif
#include "jpeg_destroyer.h"
#include "jpeg_frame.h"
+#include "jpeglib_error_wrapper.h"
#include "shared/memcpy_interleaved.h"
#include <X11/Xlib.h>
shared_ptr<Frame> decode_jpeg_vaapi(const string &jpeg)
{
jpeg_decompress_struct dinfo;
- jpeg_error_mgr jerr;
- dinfo.err = jpeg_std_error(&jerr);
- jpeg_create_decompress(&dinfo);
+ JPEGWrapErrorManager error_mgr(&dinfo);
+ if (!error_mgr.run([&dinfo] { jpeg_create_decompress(&dinfo); })) {
+ return nullptr;
+ }
JPEGDestroyer destroy_dinfo(&dinfo);
jpeg_mem_src(&dinfo, reinterpret_cast<const unsigned char *>(jpeg.data()), jpeg.size());
- jpeg_read_header(&dinfo, true);
+ if (!error_mgr.run([&dinfo] { jpeg_read_header(&dinfo, true); })) {
+ return nullptr;
+ }
if (dinfo.num_components != 3) {
fprintf(stderr, "Not a color JPEG. (%d components, Y=%dx%d, Cb=%dx%d, Cr=%dx%d)\n",