1 files changed, 25 insertions, 3 deletions
diff --git a/lib/extras/dec/pnm.h b/lib/extras/dec/pnm.h
index f637483..9b68e56 100644
--- a/lib/extras/dec/pnm.h
+++ b/lib/extras/dec/pnm.h
@@ -17,21 +17,43 @@
 #include "lib/extras/dec/color_hints.h"
 #include "lib/extras/packed_image.h"
 #include "lib/jxl/base/data_parallel.h"
-#include "lib/jxl/base/padded_bytes.h"
 #include "lib/jxl/base/span.h"
 #include "lib/jxl/base/status.h"
-#include "lib/jxl/codec_in_out.h"
 
 namespace jxl {
+
+struct SizeConstraints;
+
 namespace extras {
 
 // Decodes `bytes` into `ppf`. color_hints may specify "color_space", which
 // defaults to sRGB.
 Status DecodeImagePNM(Span<const uint8_t> bytes, const ColorHints& color_hints,
-                      const SizeConstraints& constraints, PackedPixelFile* ppf);
+                      PackedPixelFile* ppf,
+                      const SizeConstraints* constraints = nullptr);
 
 void TestCodecPNM();
 
+struct HeaderPNM {
+  size_t xsize;
+  size_t ysize;
+  bool is_gray;    // PGM
+  bool has_alpha;  // PAM
+  size_t bits_per_sample;
+  bool floating_point;
+  bool big_endian;
+  std::vector<JxlExtraChannelType> ec_types;  // PAM
+};
+
+struct ChunkedPNMDecoder {
+  FILE* f;
+  HeaderPNM header = {};
+  size_t data_start;
+};
+
+Status DecodeImagePNM(ChunkedPNMDecoder* dec, const ColorHints& color_hints,
+                      PackedPixelFile* ppf);
+
 }  // namespace extras
 }  // namespace jxl