diff --git a/Tests/images/p_4_planes.pcx b/Tests/images/p_4_planes.pcx new file mode 100644 index 000000000..8c5743a98 Binary files /dev/null and b/Tests/images/p_4_planes.pcx differ diff --git a/Tests/test_file_pcx.py b/Tests/test_file_pcx.py index 5d7fd1c1b..2e999eff6 100644 --- a/Tests/test_file_pcx.py +++ b/Tests/test_file_pcx.py @@ -37,6 +37,11 @@ def test_sanity(tmp_path: Path) -> None: im.save(f) +def test_p_4_planes() -> None: + with Image.open("Tests/images/p_4_planes.pcx") as im: + assert im.getpixel((0, 0)) == 3 + + def test_bad_image_size() -> None: with open("Tests/images/pil184.pcx", "rb") as fp: data = fp.read() diff --git a/src/libImaging/PcxDecode.c b/src/libImaging/PcxDecode.c index 942c8dc22..a65952fb1 100644 --- a/src/libImaging/PcxDecode.c +++ b/src/libImaging/PcxDecode.c @@ -60,15 +60,25 @@ ImagingPcxDecode(Imaging im, ImagingCodecState state, UINT8 *buf, Py_ssize_t byt } if (state->x >= state->bytes) { - if (state->bytes % state->xsize && state->bytes > state->xsize) { - int bands = state->bytes / state->xsize; - int stride = state->bytes / bands; + int bands; + int xsize = 0; + int stride = 0; + if (state->bits == 2 || state->bits == 4) { + xsize = (state->xsize + 7) / 8; + bands = state->bits; + stride = state->bytes / state->bits; + } else { + xsize = state->xsize; + bands = state->bytes / state->xsize; + if (bands != 0) { + stride = state->bytes / bands; + } + } + if (stride > xsize) { int i; for (i = 1; i < bands; i++) { // note -- skipping first band memmove( - &state->buffer[i * state->xsize], - &state->buffer[i * stride], - state->xsize + &state->buffer[i * xsize], &state->buffer[i * stride], xsize ); } }