Remove decoder param of avifCodecGetNextImageFunc

Remove the decoder parameter of avifCodecGetNextImageFunc so that the
avifCodec struct is independent of the avifDecoder struct.

Add the maxThreads and imageSizeLimit fields to the avifCodec struct so
that they remain available to avifCodecGetNextImageFunc.

This allows us to remove the avifDecoder local variable in
avifEncoderDecodeSatoBaseImage().

include/avif/internal.h

@@ -573,7 +573,6 @@ typedef enum avifEncoderChange
 typedef int avifEncoderChanges;
 
 typedef avifBool (*avifCodecGetNextImageFunc)(struct avifCodec * codec,
-                                              struct avifDecoder * decoder,
                                               const avifDecodeSample * sample,
                                               avifBool alpha,
                                               avifBool * isLimitedRangeAlpha,
@@ -618,9 +617,12 @@ typedef struct avifCodec
     struct avifCodecInternal * internal;  // up to each codec to use how it wants
                                           //
     avifDiagnostics * diag;               // Shallow copy; owned by avifEncoder or avifDecoder
-                                          //
-    uint8_t operatingPoint;               // Operating point, defaults to 0.
-    avifBool allLayers;                   // if true, the underlying codec must decode all layers, not just the best layer
+
+    // Decoder options (for getNextImage):
+    int maxThreads;          // See avifDecoder::maxThreads.
+    uint32_t imageSizeLimit; // See avifDecoder::imageSizeLimit.
+    uint8_t operatingPoint;  // Operating point, defaults to 0.
+    avifBool allLayers;      // if true, the underlying codec must decode all layers, not just the best layer
 
     avifCodecGetNextImageFunc getNextImage;
     avifCodecEncodeImageFunc encodeImage;

src/codec_aom.c

@@ -91,7 +91,6 @@ static void aomCodecDestroyInternal(avifCodec * codec)
 #if defined(AVIF_CODEC_AOM_DECODE)
 
 static avifBool aomCodecGetNextImage(struct avifCodec * codec,
-                                     struct avifDecoder * decoder,
                                      const avifDecodeSample * sample,
                                      avifBool alpha,
                                      avifBool * isLimitedRangeAlpha,
@@ -100,7 +99,7 @@ static avifBool aomCodecGetNextImage(struct avifCodec * codec,
     if (!codec->internal->decoderInitialized) {
         aom_codec_dec_cfg_t cfg;
         memset(&cfg, 0, sizeof(aom_codec_dec_cfg_t));
-        cfg.threads = decoder->maxThreads;
+        cfg.threads = codec->maxThreads;
         cfg.allow_lowbitdepth = 1;
 
         aom_codec_iface_t * decoder_interface = aom_codec_av1_dx();

src/codec_avm.c

@@ -53,7 +53,6 @@ static avifResult avifCheckCodecVersionAVM()
 }
 
 static avifBool avmCodecGetNextImage(struct avifCodec * codec,
-                                     struct avifDecoder * decoder,
                                      const avifDecodeSample * sample,
                                      avifBool alpha,
                                      avifBool * isLimitedRangeAlpha,
@@ -64,7 +63,7 @@ static avifBool avmCodecGetNextImage(struct avifCodec * codec,
 
         aom_codec_dec_cfg_t cfg;
         memset(&cfg, 0, sizeof(aom_codec_dec_cfg_t));
-        cfg.threads = decoder->maxThreads;
+        cfg.threads = codec->maxThreads;
 
         aom_codec_iface_t * decoder_interface = aom_codec_av1_dx();
         if (aom_codec_dec_init(&codec->internal->decoder, decoder_interface, &cfg, 0)) {

src/codec_dav1d.c

@@ -49,7 +49,6 @@ static void dav1dCodecDestroyInternal(avifCodec * codec)
 }
 
 static avifBool dav1dCodecGetNextImage(struct avifCodec * codec,
-                                       struct avifDecoder * decoder,
                                        const avifDecodeSample * sample,
                                        avifBool alpha,
                                        avifBool * isLimitedRangeAlpha,
@@ -61,16 +60,16 @@ static avifBool dav1dCodecGetNextImage(struct avifCodec * codec,
         // Give all available threads to decode a single frame as fast as possible
 #if DAV1D_API_VERSION_MAJOR >= 6
         dav1dSettings.max_frame_delay = 1;
-        dav1dSettings.n_threads = AVIF_CLAMP(decoder->maxThreads, 1, DAV1D_MAX_THREADS);
+        dav1dSettings.n_threads = AVIF_CLAMP(codec->maxThreads, 1, DAV1D_MAX_THREADS);
 #else
         dav1dSettings.n_frame_threads = 1;
-        dav1dSettings.n_tile_threads = AVIF_CLAMP(decoder->maxThreads, 1, DAV1D_MAX_TILE_THREADS);
+        dav1dSettings.n_tile_threads = AVIF_CLAMP(codec->maxThreads, 1, DAV1D_MAX_TILE_THREADS);
 #endif // DAV1D_API_VERSION_MAJOR >= 6
         // Set a maximum frame size limit to avoid OOM'ing fuzzers. In 32-bit builds, if
         // frame_size_limit > 8192 * 8192, dav1d reduces frame_size_limit to 8192 * 8192 and logs
         // a message, so we set frame_size_limit to at most 8192 * 8192 to avoid the dav1d_log
         // message.
-        dav1dSettings.frame_size_limit = (sizeof(size_t) < 8) ? AVIF_MIN(decoder->imageSizeLimit, 8192 * 8192) : decoder->imageSizeLimit;
+        dav1dSettings.frame_size_limit = (sizeof(size_t) < 8) ? AVIF_MIN(codec->imageSizeLimit, 8192 * 8192) : codec->imageSizeLimit;
         dav1dSettings.operating_point = codec->operatingPoint;
         dav1dSettings.all_layers = codec->allLayers;
 

src/codec_libgav1.c

@@ -24,14 +24,13 @@ static void gav1CodecDestroyInternal(avifCodec * codec)
 }
 
 static avifBool gav1CodecGetNextImage(struct avifCodec * codec,
-                                      struct avifDecoder * decoder,
                                       const avifDecodeSample * sample,
                                       avifBool alpha,
                                       avifBool * isLimitedRangeAlpha,
                                       avifImage * image)
 {
     if (codec->internal->gav1Decoder == NULL) {
-        codec->internal->gav1Settings.threads = decoder->maxThreads;
+        codec->internal->gav1Settings.threads = codec->maxThreads;
         codec->internal->gav1Settings.operating_point = codec->operatingPoint;
         codec->internal->gav1Settings.output_all_layers = codec->allLayers;
 

src/read.c

@@ -5711,7 +5711,9 @@ static avifResult avifDecoderDecodeTiles(avifDecoder * decoder, uint32_t nextIma
         }
 
         avifBool isLimitedRangeAlpha = AVIF_FALSE;
-        if (!tile->codec->getNextImage(tile->codec, decoder, sample, avifIsAlpha(tile->input->itemCategory), &isLimitedRangeAlpha, tile->image)) {
+        tile->codec->maxThreads = decoder->maxThreads;
+        tile->codec->imageSizeLimit = decoder->imageSizeLimit;
+        if (!tile->codec->getNextImage(tile->codec, sample, avifIsAlpha(tile->input->itemCategory), &isLimitedRangeAlpha, tile->image)) {
             avifDiagnosticsPrintf(&decoder->diag, "tile->codec->getNextImage() failed");
             return avifGetErrorForItemCategory(tile->input->itemCategory);
         }

src/write.c

@@ -1331,17 +1331,13 @@ static avifResult avifEncoderDecodeSatoBaseImage(avifEncoder * encoder,
     }
     AVIF_ASSERT_OR_RETURN(sample.data.size != 0); // There should be at least one base item.
 
-    // avifCodecGetNextImageFunc() uses only a few fields of its decoder argument.
-    avifDecoder decoder;
-    memset(&decoder, 0, sizeof(decoder));
-    decoder.maxThreads = encoder->maxThreads;
-    decoder.imageSizeLimit = AVIF_DEFAULT_IMAGE_SIZE_LIMIT;
-
     AVIF_CHECKRES(avifCodecCreate(AVIF_CODEC_CHOICE_AUTO, AVIF_CODEC_FLAG_CAN_DECODE, codec));
     (*codec)->diag = &encoder->diag;
+    (*codec)->maxThreads = encoder->maxThreads;
+    (*codec)->imageSizeLimit = AVIF_DEFAULT_IMAGE_SIZE_LIMIT;
     AVIF_CHECKRES(avifImageCreateAllocate(decodedBaseImage, original, numBits, planes));
     avifBool isLimitedRangeAlpha = AVIF_FALSE; // Ignored.
-    AVIF_CHECKERR((*codec)->getNextImage(*codec, &decoder, &sample, planes == AVIF_PLANES_A, &isLimitedRangeAlpha, *decodedBaseImage),
+    AVIF_CHECKERR((*codec)->getNextImage(*codec, &sample, planes == AVIF_PLANES_A, &isLimitedRangeAlpha, *decodedBaseImage),
                   AVIF_RESULT_ENCODE_SAMPLE_TRANSFORM_FAILED);
     return AVIF_RESULT_OK;
 }