MeshCentral/MeshAgent
1
0
Fork 0
mirror of https://github.com/Ylianst/MeshAgent synced 2025-12-17 08:43:21 +00:00
Code Issues Releases Wiki Activity

Fixed JPEG chroma subsampling on TurboLibJPEG

Browse Source
This commit is contained in:
Ylian Saint-Hilaire
2021-03-25 16:58:15 -07:00
parent 0c1358a9ac
commit 6c36f2fa6b
1 changed files with 14 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
meshcore/KVM/Linux/linux_compression.c
View File

@@ -83,7 +83,7 @@ void term_destination (j_compress_ptr cinfo)
} }
} }
int write_JPEG_buffer (JSAMPLE * image_buffer, int image_width, int image_height, int quality) int write_JPEG_buffer(JSAMPLE * image_buffer, int image_width, int image_height, int quality)
{ {
struct jpeg_compress_struct cinfo; struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr; struct jpeg_error_mgr jerr;
@@ -94,26 +94,34 @@ int write_JPEG_buffer (JSAMPLE * image_buffer, int image_width, int image_height
if (default_JPEG_error_handler != NULL) { jerr.error_exit = jpeg_error_handler; } if (default_JPEG_error_handler != NULL) { jerr.error_exit = jpeg_error_handler; }
jpeg_create_compress(&cinfo); jpeg_create_compress(&cinfo);
cinfo.dest = (struct jpeg_destination_mgr *) malloc (sizeof(struct jpeg_destination_mgr)); cinfo.dest = (struct jpeg_destination_mgr *) malloc(sizeof(struct jpeg_destination_mgr));
cinfo.dest->init_destination = &init_destination; cinfo.dest->init_destination = &init_destination;
cinfo.dest->empty_output_buffer = &empty_output_buffer; cinfo.dest->empty_output_buffer = &empty_output_buffer;
cinfo.dest->term_destination = &term_destination; cinfo.dest->term_destination = &term_destination;
cinfo.comp_info[0].v_samp_factor = 1;
cinfo.comp_info[0].h_samp_factor = 1;
cinfo.image_width = image_width; cinfo.image_width = image_width;
cinfo.image_height = image_height; cinfo.image_height = image_height;
cinfo.input_components = 3; cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB; cinfo.in_color_space = JCS_RGB;
jpeg_set_defaults(&cinfo); jpeg_set_defaults(&cinfo);
// 4:4:4, 1x1 (no subsampling)
// The resolution of chrominance information (Cb & Cr) is preserved at the same rate as the luminance (Y) information
cinfo.comp_info[0].v_samp_factor = 1;
cinfo.comp_info[0].h_samp_factor = 1;
cinfo.comp_info[1].v_samp_factor = 1;
cinfo.comp_info[1].h_samp_factor = 1;
cinfo.comp_info[2].v_samp_factor = 1;
cinfo.comp_info[2].h_samp_factor = 1;
jpeg_set_quality(&cinfo, quality, TRUE); jpeg_set_quality(&cinfo, quality, TRUE);
jpeg_start_compress(&cinfo, TRUE); jpeg_start_compress(&cinfo, TRUE);
row_stride = image_width * 3; row_stride = image_width * 3;
while (cinfo.next_scanline < cinfo.image_height) while (cinfo.next_scanline < cinfo.image_height)
{ {
row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride]; row_pointer[0] = &image_buffer[cinfo.next_scanline * row_stride];
(void) jpeg_write_scanlines(&cinfo, row_pointer, 1); (void)jpeg_write_scanlines(&cinfo, row_pointer, 1);
} }
jpeg_finish_compress(&cinfo); jpeg_finish_compress(&cinfo);
@@ -124,4 +132,3 @@ int write_JPEG_buffer (JSAMPLE * image_buffer, int image_width, int image_height
return 0; return 0;
} }