decoder: added CS override opt for FF JPEGs

FFmpeg encoded JPEGs with COM CS=ITU601 are limited-range BT.601. Allow
override when the caller knows that it is actually limiee-range BT.709
as eg. UltraGrid does.

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.8.0 FATAL_ERROR)
 # change version also in configure.ac
-project(gpujpeg VERSION 0.25.4 LANGUAGES C CUDA)
+project(gpujpeg VERSION 0.25.5 LANGUAGES C CUDA)
 
 # options
 set(BUILD_OPENGL OFF CACHE STRING "Build with OpenGL support, options are: AUTO ON OFF")

NEWS.md

@@ -1,7 +1,10 @@
 2024-10-08 - 0.25.5
 ----------
-- add gpujpeg_decoder_create_with_params() (+ struct
+- added gpujpeg_decoder_create_with_params() (+ struct
   gpujpeg_decoder_init_parameters, gpujpeg_decoder_default_init_parameters())
+- added gpujpeg_decoder_init_parameters.ff_cs_itu601_is_709 flag to
+  override colorspace to limited 709 if FFmpeg-specific comment CS=ITU601
+  is present (as 709 is used by UltraGrid)
 
 2024-10-07 - 0.25.4
 ----------
@@ -10,7 +13,7 @@
 2024-06-05 - 0.25.3
 ----------
 - added gpujpeg_color_space_by_name
-- addeg gpujpeg_print_pixel_format
+- added gpujpeg_print_pixel_format
 
 2024-04-09 - 0.25.2
 ----------

libgpujpeg/gpujpeg_decoder.h

@@ -90,6 +90,8 @@ struct gpujpeg_decoder_init_parameters
     cudaStream_t stream; ///< stream CUDA stream to be used, cudaStreamDefault (0x00) is default
     int verbose; ///< verbosity level (-1 - quiet, 0 - normal, 1 - verbose)
     bool perf_stats; ///< print performance statistics on output
+    bool ff_cs_itu601_is_709; ///< if FFmpeg specific COM marker "CS=ITU601" present, interpret the data as
+                              ///< limited-range BT.709 not BT.601
 };
 
 /**

src/gpujpeg_decoder.c

@@ -157,7 +157,7 @@ gpujpeg_decoder_create(cudaStream_t stream)
 struct gpujpeg_decoder_init_parameters
 gpujpeg_decoder_default_init_parameters()
 {
-    return (struct gpujpeg_decoder_init_parameters){cudaStreamDefault, 0, false};
+    return (struct gpujpeg_decoder_init_parameters){cudaStreamDefault, 0, false, false};
 }
 /**
  * Create JPEG decoder
@@ -174,6 +174,7 @@ gpujpeg_decoder_create_with_params(const struct gpujpeg_decoder_init_parameters
     }
     decoder->coder.param.verbose = params->verbose;
     decoder->coder.param.perf_stats = params->perf_stats;
+    decoder->ff_cs_itu601_is_709 = params->ff_cs_itu601_is_709;
     return decoder;
 }
 

src/gpujpeg_decoder_internal.h

@@ -31,6 +31,8 @@
 #ifndef GPUJPEG_DECODER_INTERNAL_H
 #define GPUJPEG_DECODER_INTERNAL_H
 
+#include <stdbool.h>
+
 #include "../libgpujpeg/gpujpeg_common.h"
 #include "gpujpeg_common_internal.h"
 #include "gpujpeg_table.h"
@@ -68,6 +70,8 @@ struct gpujpeg_decoder
 
     enum gpujpeg_pixel_format req_pixel_format;
     enum gpujpeg_color_space req_color_space;
+    bool ff_cs_itu601_is_709; ///< if FFmpeg specific COM marker "CS=ITU601" present, interpret the data as
+                              ///< limited-range BT.709 not BT.601
 };
 
 #endif // GPUJPEG_DECODER_INTERNAL_H

src/gpujpeg_reader.c

@@ -31,6 +31,7 @@
 #include <ctype.h>
 #include <inttypes.h>
 #include <string.h>
+#include <stdbool.h>
 
 #include "../libgpujpeg/gpujpeg_decoder.h"
 #include "gpujpeg_decoder_internal.h"
@@ -578,7 +579,8 @@ gpujpeg_reader_read_app14(uint8_t** image, const uint8_t* image_end, enum gpujpe
 }
 
 static int
-gpujpeg_reader_read_com(uint8_t** image, const uint8_t* image_end, enum gpujpeg_color_space *color_space)
+gpujpeg_reader_read_com(uint8_t** image, const uint8_t* image_end, bool ff_cs_itu601_is_709,
+                        enum gpujpeg_color_space* color_space)
 {
     if(image_end - *image < 2) {
         fprintf(stderr, "[GPUJPEG] [Error] Could not read com length\n");
@@ -596,7 +598,7 @@ gpujpeg_reader_read_com(uint8_t** image, const uint8_t* image_end, enum gpujpeg_
     const size_t com_length = length - 2; // check both with '\0' and without:
     if ( (com_length == sizeof cs_itu601 || com_length == sizeof cs_itu601 - 1) &&
          strncmp((char*)*image, cs_itu601, com_length) == 0 ) {
-        *color_space = GPUJPEG_YCBCR_BT601;
+        *color_space = ff_cs_itu601_is_709 ? GPUJPEG_YCBCR_BT709 : GPUJPEG_YCBCR_BT601;
     }
 
     *image += length - 2;
@@ -1232,7 +1234,9 @@ gpujpeg_reader_read_sos(struct gpujpeg_decoder* decoder, struct gpujpeg_reader*
  * @retval @ref Errors
  */
 static int
-gpujpeg_reader_read_common_markers(uint8_t **image, const uint8_t* image_end, int marker, int log_level, enum gpujpeg_color_space *color_space, int *restart_interval, _Bool *in_spiff)
+gpujpeg_reader_read_common_markers(uint8_t** image, const uint8_t* image_end, int marker, int log_level,
+                                   bool ff_cs_itu601_is_709, enum gpujpeg_color_space* color_space,
+                                   int* restart_interval, bool* in_spiff)
 {
     int rc = 0;
     switch (marker)
@@ -1310,7 +1314,7 @@ gpujpeg_reader_read_common_markers(uint8_t **image, const uint8_t* image_end, in
             return -1;
 
         case GPUJPEG_MARKER_COM:
-            if ( gpujpeg_reader_read_com(image, image_end, color_space) != 0 ) {
+            if ( gpujpeg_reader_read_com(image, image_end, ff_cs_itu601_is_709, color_space) != 0 ) {
                 return -1;
             }
             break;
@@ -1420,8 +1424,9 @@ gpujpeg_reader_read_image(struct gpujpeg_decoder* decoder, uint8_t* image, size_
         }
 
         // Read more info according to the marker
-        int rc = gpujpeg_reader_read_common_markers(&image, image_end, marker, decoder->coder.param.verbose, &header_color_space, &reader.param.restart_interval, &in_spiff);
-        if (rc < 0) {
+        int rc = gpujpeg_reader_read_common_markers(&image, image_end, marker, decoder->coder.param.verbose, decoder->ff_cs_itu601_is_709,
+                                                    &header_color_space, &reader.param.restart_interval, &in_spiff);
+        if ( rc < 0 ) {
             return rc;
         }
         if (rc == 0) { // already processed
@@ -1547,8 +1552,9 @@ gpujpeg_reader_get_image_info(uint8_t *image, size_t image_size, struct gpujpeg_
         }
 
         // Read more info according to the marker
-        int rc = gpujpeg_reader_read_common_markers(&image, image_end, marker, param->verbose, &header_color_space, &param->restart_interval, &in_spiff);
-        if (rc < 0) {
+        int rc = gpujpeg_reader_read_common_markers(&image, image_end, marker, param->verbose, false,
+                                                    &header_color_space, &param->restart_interval, &in_spiff);
+        if ( rc < 0 ) {
             return rc;
         }
         if (rc == 0) { // already processed