diff --git a/src/decode.c b/src/decode.c
index 51d0aced2..1e9906ae7 100644
--- a/src/decode.c
+++ b/src/decode.c
@@ -293,7 +293,7 @@ static PyTypeObject ImagingDecoderType = {
 /* -------------------------------------------------------------------- */
 
 int
-get_unpacker(ImagingDecoderObject *decoder, const char *mode, const char *rawmode) {
+get_unpacker(ImagingDecoderObject *decoder, const Mode *mode, const RawMode *rawmode) {
     int bits;
     ImagingShuffler unpack;
 
@@ -463,12 +463,14 @@ PyObject *
 PyImaging_HexDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
-    if (!PyArg_ParseTuple(args, "ss", &mode, &rawmode)) {
+    char *mode_name, *rawmode_name;
+    if (!PyArg_ParseTuple(args, "ss", &mode_name, &rawmode_name)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(0);
     if (decoder == NULL) {
         return NULL;
@@ -496,16 +498,19 @@ PyImaging_HexDecoderNew(PyObject *self, PyObject *args) {
 PyObject *
 PyImaging_LibTiffDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     char *compname;
     int fp;
     uint32_t ifdoffset;
 
-    if (!PyArg_ParseTuple(args, "sssiI", &mode, &rawmode, &compname, &fp, &ifdoffset)) {
+    if (!PyArg_ParseTuple(args, "sssiI", &mode_name, &rawmode_name, &compname, &fp, &ifdoffset)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     TRACE(("new tiff decoder %s\n", compname));
 
     decoder = PyImaging_DecoderNew(sizeof(TIFFSTATE));
@@ -538,12 +543,15 @@ PyObject *
 PyImaging_PackbitsDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
-    if (!PyArg_ParseTuple(args, "ss", &mode, &rawmode)) {
+    char *mode_name;
+    char *rawmode_name;
+    if (!PyArg_ParseTuple(args, "ss", &mode_name, &rawmode_name)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(0);
     if (decoder == NULL) {
         return NULL;
@@ -572,7 +580,7 @@ PyImaging_PcdDecoderNew(PyObject *self, PyObject *args) {
     }
 
     /* Unpack from PhotoYCC to RGB */
-    if (get_unpacker(decoder, "RGB", "YCC;P") < 0) {
+    if (get_unpacker(decoder, IMAGING_MODE_RGB, IMAGING_RAWMODE_YCC_P) < 0) {
         return NULL;
     }
 
@@ -589,13 +597,15 @@ PyObject *
 PyImaging_PcxDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name, *rawmode_name;
     int stride;
-    if (!PyArg_ParseTuple(args, "ssi", &mode, &rawmode, &stride)) {
+    if (!PyArg_ParseTuple(args, "ssi", &mode_name, &rawmode_name, &stride)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(0);
     if (decoder == NULL) {
         return NULL;
@@ -620,14 +630,16 @@ PyObject *
 PyImaging_RawDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name, *rawmode_name;
     int stride = 0;
     int ystep = 1;
-    if (!PyArg_ParseTuple(args, "ss|ii", &mode, &rawmode, &stride, &ystep)) {
+    if (!PyArg_ParseTuple(args, "ss|ii", &mode_name, &rawmode_name, &stride, &ystep)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(sizeof(RAWSTATE));
     if (decoder == NULL) {
         return NULL;
@@ -654,14 +666,16 @@ PyObject *
 PyImaging_SgiRleDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name, *rawmode_name;
     int ystep = 1;
     int bpc = 1;
-    if (!PyArg_ParseTuple(args, "ss|ii", &mode, &rawmode, &ystep, &bpc)) {
+    if (!PyArg_ParseTuple(args, "ss|ii", &mode_name, &rawmode_name, &ystep, &bpc)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(sizeof(SGISTATE));
     if (decoder == NULL) {
         return NULL;
@@ -688,12 +702,14 @@ PyObject *
 PyImaging_SunRleDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
-    if (!PyArg_ParseTuple(args, "ss", &mode, &rawmode)) {
+    char *mode_name, *rawmode_name;
+    if (!PyArg_ParseTuple(args, "ss", &mode_name, &rawmode_name)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(0);
     if (decoder == NULL) {
         return NULL;
@@ -716,14 +732,16 @@ PyObject *
 PyImaging_TgaRleDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name, *rawmode_name;
     int ystep = 1;
     int depth = 8;
-    if (!PyArg_ParseTuple(args, "ss|ii", &mode, &rawmode, &ystep, &depth)) {
+    if (!PyArg_ParseTuple(args, "ss|ii", &mode_name, &rawmode_name, &ystep, &depth)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(0);
     if (decoder == NULL) {
         return NULL;
@@ -754,7 +772,7 @@ PyImaging_XbmDecoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
-    if (get_unpacker(decoder, "1", "1;R") < 0) {
+    if (get_unpacker(decoder, IMAGING_MODE_1, IMAGING_RAWMODE_1_R) < 0) {
         return NULL;
     }
 
@@ -775,13 +793,15 @@ PyObject *
 PyImaging_ZipDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name, *rawmode_name;
     int interlaced = 0;
-    if (!PyArg_ParseTuple(args, "ss|i", &mode, &rawmode, &interlaced)) {
+    if (!PyArg_ParseTuple(args, "ss|i", &mode_name, &rawmode_name, &interlaced)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     decoder = PyImaging_DecoderNew(sizeof(ZIPSTATE));
     if (decoder == NULL) {
         return NULL;
@@ -825,16 +845,19 @@ PyObject *
 PyImaging_JpegDecoderNew(PyObject *self, PyObject *args) {
     ImagingDecoderObject *decoder;
 
-    char *mode;
-    char *rawmode;  /* what we want from the decoder */
-    char *jpegmode; /* what's in the file */
+    char *mode_name;
+    char *rawmode_name; /* what we want from the decoder */
+    char *jpegmode;     /* what's in the file */
     int scale = 1;
     int draft = 0;
 
-    if (!PyArg_ParseTuple(args, "ssz|ii", &mode, &rawmode, &jpegmode, &scale, &draft)) {
+    if (!PyArg_ParseTuple(args, "ssz|ii", &mode_name, &rawmode_name, &jpegmode, &scale, &draft)) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * rawmode = findRawMode(rawmode_name);
+
     if (!jpegmode) {
         jpegmode = "";
     }
@@ -847,8 +870,8 @@ PyImaging_JpegDecoderNew(PyObject *self, PyObject *args) {
     // libjpeg-turbo supports different output formats.
     // We are choosing Pillow's native format (3 color bytes + 1 padding)
     // to avoid extra conversion in Unpack.c.
-    if (ImagingJpegUseJCSExtensions() && strcmp(rawmode, "RGB") == 0) {
-        rawmode = "RGBX";
+    if (ImagingJpegUseJCSExtensions() && rawmode == IMAGING_RAWMODE_RGB) {
+        rawmode = IMAGING_RAWMODE_RGBX;
     }
 
     if (get_unpacker(decoder, mode, rawmode) < 0) {
@@ -858,11 +881,13 @@ PyImaging_JpegDecoderNew(PyObject *self, PyObject *args) {
     decoder->decode = ImagingJpegDecode;
     decoder->cleanup = ImagingJpegDecodeCleanup;
 
-    strncpy(((JPEGSTATE *)decoder->state.context)->rawmode, rawmode, 8);
-    strncpy(((JPEGSTATE *)decoder->state.context)->jpegmode, jpegmode, 8);
+    JPEGSTATE *jpeg_decoder_state_context = (JPEGSTATE *)decoder->state.context;
 
-    ((JPEGSTATE *)decoder->state.context)->scale = scale;
-    ((JPEGSTATE *)decoder->state.context)->draft = draft;
+    jpeg_decoder_state_context->rawmode = rawmode;
+    strncpy(jpeg_decoder_state_context->jpegmode, jpegmode, 8);
+
+    jpeg_decoder_state_context->scale = scale;
+    jpeg_decoder_state_context->draft = draft;
 
     return (PyObject *)decoder;
 }
diff --git a/src/encode.c b/src/encode.c
index 1a4cd489d..c8a5c463e 100644
--- a/src/encode.c
+++ b/src/encode.c
@@ -360,14 +360,19 @@ static PyTypeObject ImagingEncoderType = {
 /* -------------------------------------------------------------------- */
 
 int
-get_packer(ImagingEncoderObject *encoder, const char *mode, const char *rawmode) {
+get_packer(ImagingEncoderObject *encoder, const Mode *mode, const RawMode *rawmode) {
     int bits;
     ImagingShuffler pack;
 
     pack = ImagingFindPacker(mode, rawmode, &bits);
     if (!pack) {
         Py_DECREF(encoder);
-        PyErr_Format(PyExc_ValueError, "No packer found from %s to %s", mode, rawmode);
+        PyErr_Format(
+            PyExc_ValueError,
+            "No packer found from %s to %s",
+            mode->name,
+            rawmode->name
+        );
         return -1;
     }
 
@@ -403,11 +408,11 @@ PyObject *
 PyImaging_GifEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t bits = 8;
     Py_ssize_t interlace = 0;
-    if (!PyArg_ParseTuple(args, "ss|nn", &mode, &rawmode, &bits, &interlace)) {
+    if (!PyArg_ParseTuple(args, "ss|nn", &mode_name, &rawmode_name, &bits, &interlace)) {
         return NULL;
     }
 
@@ -416,6 +421,9 @@ PyImaging_GifEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         return NULL;
     }
@@ -436,11 +444,11 @@ PyObject *
 PyImaging_PcxEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t bits = 8;
 
-    if (!PyArg_ParseTuple(args, "ss|n", &mode, &rawmode, &bits)) {
+    if (!PyArg_ParseTuple(args, "ss|n", &mode_name, &rawmode_name, &bits)) {
         return NULL;
     }
 
@@ -449,6 +457,9 @@ PyImaging_PcxEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         return NULL;
     }
@@ -466,12 +477,12 @@ PyObject *
 PyImaging_RawEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t stride = 0;
     Py_ssize_t ystep = 1;
 
-    if (!PyArg_ParseTuple(args, "ss|nn", &mode, &rawmode, &stride, &ystep)) {
+    if (!PyArg_ParseTuple(args, "ss|nn", &mode_name, &rawmode_name, &stride, &ystep)) {
         return NULL;
     }
 
@@ -480,6 +491,9 @@ PyImaging_RawEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         return NULL;
     }
@@ -500,11 +514,11 @@ PyObject *
 PyImaging_TgaRleEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t ystep = 1;
 
-    if (!PyArg_ParseTuple(args, "ss|n", &mode, &rawmode, &ystep)) {
+    if (!PyArg_ParseTuple(args, "ss|n", &mode_name, &rawmode_name, &ystep)) {
         return NULL;
     }
 
@@ -513,6 +527,9 @@ PyImaging_TgaRleEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         return NULL;
     }
@@ -537,7 +554,7 @@ PyImaging_XbmEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
-    if (get_packer(encoder, "1", "1;R") < 0) {
+    if (get_packer(encoder, IMAGING_MODE_1, IMAGING_RAWMODE_1_R) < 0) {
         return NULL;
     }
 
@@ -558,8 +575,8 @@ PyObject *
 PyImaging_ZipEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t optimize = 0;
     Py_ssize_t compress_level = -1;
     Py_ssize_t compress_type = -1;
@@ -568,8 +585,8 @@ PyImaging_ZipEncoderNew(PyObject *self, PyObject *args) {
     if (!PyArg_ParseTuple(
             args,
             "ss|nnny#",
-            &mode,
-            &rawmode,
+            &mode_name,
+            &rawmode_name,
             &optimize,
             &compress_level,
             &compress_type,
@@ -598,6 +615,9 @@ PyImaging_ZipEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         free(dictionary);
         return NULL;
@@ -606,7 +626,7 @@ PyImaging_ZipEncoderNew(PyObject *self, PyObject *args) {
     encoder->encode = ImagingZipEncode;
     encoder->cleanup = ImagingZipEncodeCleanup;
 
-    if (rawmode[0] == 'P') {
+    if (rawmode == IMAGING_RAWMODE_P || rawmode == IMAGING_RAWMODE_PA) {
         /* disable filtering */
         ((ZIPSTATE *)encoder->state.context)->mode = ZIP_PNG_PALETTE;
     }
@@ -635,8 +655,8 @@ PyObject *
 PyImaging_LibTiffEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     char *compname;
     char *filename;
     Py_ssize_t fp;
@@ -656,7 +676,15 @@ PyImaging_LibTiffEncoderNew(PyObject *self, PyObject *args) {
     PyObject *item;
 
     if (!PyArg_ParseTuple(
-            args, "sssnsOO", &mode, &rawmode, &compname, &fp, &filename, &tags, &types
+            args,
+            "sssnsOO",
+            &mode_name,
+            &rawmode_name,
+            &compname,
+            &fp,
+            &filename,
+            &tags,
+            &types
         )) {
         return NULL;
     }
@@ -694,6 +722,9 @@ PyImaging_LibTiffEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * const rawmode = findRawMode(rawmode_name);
+
     if (get_packer(encoder, mode, rawmode) < 0) {
         return NULL;
     }
@@ -1071,8 +1102,8 @@ PyObject *
 PyImaging_JpegEncoderNew(PyObject *self, PyObject *args) {
     ImagingEncoderObject *encoder;
 
-    char *mode;
-    char *rawmode;
+    char *mode_name;
+    char *rawmode_name;
     Py_ssize_t quality = 0;
     Py_ssize_t progressive = 0;
     Py_ssize_t smooth = 0;
@@ -1096,8 +1127,8 @@ PyImaging_JpegEncoderNew(PyObject *self, PyObject *args) {
     if (!PyArg_ParseTuple(
             args,
             "ss|nnnnpnnnnnnOz#y#y#",
-            &mode,
-            &rawmode,
+            &mode_name,
+            &rawmode_name,
             &quality,
             &progressive,
             &smooth,
@@ -1125,11 +1156,14 @@ PyImaging_JpegEncoderNew(PyObject *self, PyObject *args) {
         return NULL;
     }
 
+    const Mode * const mode = findMode(mode_name);
+    const RawMode * rawmode = findRawMode(rawmode_name);
+
     // libjpeg-turbo supports different output formats.
     // We are choosing Pillow's native format (3 color bytes + 1 padding)
     // to avoid extra conversion in Pack.c.
-    if (ImagingJpegUseJCSExtensions() && strcmp(rawmode, "RGB") == 0) {
-        rawmode = "RGBX";
+    if (ImagingJpegUseJCSExtensions() && rawmode == IMAGING_RAWMODE_RGB) {
+        rawmode = IMAGING_RAWMODE_RGBX;
     }
 
     if (get_packer(encoder, mode, rawmode) < 0) {
@@ -1187,7 +1221,7 @@ PyImaging_JpegEncoderNew(PyObject *self, PyObject *args) {
     encoder->encode = ImagingJpegEncode;
 
     JPEGENCODERSTATE *jpeg_encoder_state = (JPEGENCODERSTATE *)encoder->state.context;
-    strncpy(jpeg_encoder_state->rawmode, rawmode, 8);
+    jpeg_encoder_state->rawmode = rawmode;
     jpeg_encoder_state->keep_rgb = keep_rgb;
     jpeg_encoder_state->quality = quality;
     jpeg_encoder_state->qtables = qarrays;
diff --git a/src/libImaging/Jpeg.h b/src/libImaging/Jpeg.h
index 7cdba9022..35df91d7f 100644
--- a/src/libImaging/Jpeg.h
+++ b/src/libImaging/Jpeg.h
@@ -31,9 +31,9 @@ typedef struct {
     /* Jpeg file mode (empty if not known) */
     char jpegmode[8 + 1];
 
-    /* Converter output mode (input to the shuffler).  If empty,
-       convert conversions are disabled */
-    char rawmode[8 + 1];
+    /* Converter output mode (input to the shuffler) */
+    /* If NULL, convert conversions are disabled */
+    const RawMode *rawmode;
 
     /* If set, trade quality for speed */
     int draft;
@@ -91,7 +91,7 @@ typedef struct {
     unsigned int restart_marker_rows;
 
     /* Converter input mode (input to the shuffler) */
-    char rawmode[8 + 1];
+    const RawMode *rawmode;
 
     /* Custom quantization tables () */
     unsigned int *qtables;
diff --git a/src/libImaging/Mode.h b/src/libImaging/Mode.h
index 6491beb81..a99103667 100644
--- a/src/libImaging/Mode.h
+++ b/src/libImaging/Mode.h
@@ -43,6 +43,7 @@ typedef struct {
     const char * const name;
 } RawMode;
 
+// Non-rawmode aliases.
 extern const RawMode * const IMAGING_RAWMODE_1;
 extern const RawMode * const IMAGING_RAWMODE_CMYK;
 extern const RawMode * const IMAGING_RAWMODE_F;
@@ -60,16 +61,22 @@ extern const RawMode * const IMAGING_RAWMODE_RGBX;
 extern const RawMode * const IMAGING_RAWMODE_RGBa;
 extern const RawMode * const IMAGING_RAWMODE_YCbCr;
 
+// BGR modes.
 extern const RawMode * const IMAGING_RAWMODE_BGR_15;
 extern const RawMode * const IMAGING_RAWMODE_BGR_16;
 extern const RawMode * const IMAGING_RAWMODE_BGR_24;
 extern const RawMode * const IMAGING_RAWMODE_BGR_32;
 
+// I;16 modes.
 extern const RawMode * const IMAGING_RAWMODE_I_16;
 extern const RawMode * const IMAGING_RAWMODE_I_16L;
 extern const RawMode * const IMAGING_RAWMODE_I_16B;
 extern const RawMode * const IMAGING_RAWMODE_I_16N;
 
+// Rawmodes
+extern const RawMode * const IMAGING_RAWMODE_1_R;
+extern const RawMode * const IMAGING_RAWMODE_YCC_P;
+
 const RawMode * findRawMode(const char * const name);