[FFmpeg-devel] [PATCH 06/12] ffv1dec: set f->state_transition for default range coder table
Lynne
dev at lynne.ee
Sun Jan 19 12:36:24 EET 2025
The table is only set when f->ac is set to CUSTOM. Setting it
for default range coder tables simplifies hardware accelerator code.
---
libavcodec/ffv1dec.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index 83c5975550..fdd3d1c15d 100644
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -444,6 +444,11 @@ static int read_extra_header(FFV1Context *f)
if (f->ac == AC_RANGE_CUSTOM_TAB) {
for (int i = 1; i < 256; i++)
f->state_transition[i] = get_symbol(&c, state, 1) + c.one_state[i];
+ } else {
+ RangeCoder rc;
+ ff_build_rac_states(&rc, 0.05 * (1LL << 32), 256 - 8);
+ for (int i = 1; i < 256; i++)
+ f->state_transition[i] = rc.one_state[i];
}
f->colorspace = get_symbol(&c, state, 0); //YUV cs type
@@ -574,6 +579,11 @@ static int read_header(FFV1Context *f, RangeCoder *c)
}
f->state_transition[i] = st;
}
+ } else {
+ RangeCoder rc;
+ ff_build_rac_states(&rc, 0.05 * (1LL << 32), 256 - 8);
+ for (int i = 1; i < 256; i++)
+ f->state_transition[i] = rc.one_state[i];
}
colorspace = get_symbol(c, state, 0); //YUV cs type
--
2.47.1
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