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From a9e9303f26597b2a166374cd46b00adc0401e634 Mon Sep 17 00:00:00 2001
From: James Almer <jamrial@gmail.com>
Date: Sat, 10 Nov 2018 22:52:12 -0300
Subject: [PATCH] avcodec/cbs_av1: fix parsing signed integer values
Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: James Almer <jamrial@gmail.com>
(cherry picked from commit f0f2832a5ce93bad9b1d29f99df6bda2380fc41c)
---
libavcodec/cbs_av1.c | 30 +++++++++---------------------
1 file changed, 9 insertions(+), 21 deletions(-)
diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c
index ff32a6f..ed5211b 100644
--- a/libavcodec/cbs_av1.c
+++ b/libavcodec/cbs_av1.c
@@ -189,30 +189,26 @@ static int cbs_av1_read_su(CodedBitstreamContext *ctx, GetBitContext *gbc,
int width, const char *name,
const int *subscripts, int32_t *write_to)
{
- uint32_t magnitude;
- int position, sign;
+ int position;
int32_t value;
if (ctx->trace_enable)
position = get_bits_count(gbc);
- if (get_bits_left(gbc) < width + 1) {
+ if (get_bits_left(gbc) < width) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid signed value at "
"%s: bitstream ended.\n", name);
return AVERROR_INVALIDDATA;
}
- magnitude = get_bits(gbc, width);
- sign = get_bits1(gbc);
- value = sign ? -(int32_t)magnitude : magnitude;
+ value = get_sbits(gbc, width);
if (ctx->trace_enable) {
char bits[33];
int i;
for (i = 0; i < width; i++)
- bits[i] = magnitude >> (width - i - 1) & 1 ? '1' : '0';
- bits[i] = sign ? '1' : '0';
- bits[i + 1] = 0;
+ bits[i] = value & (1 << (width - i - 1)) ? '1' : '0';
+ bits[i] = 0;
ff_cbs_trace_syntax_element(ctx, position,
name, subscripts, bits, value);
@@ -226,29 +222,21 @@ static int cbs_av1_write_su(CodedBitstreamContext *ctx, PutBitContext *pbc,
int width, const char *name,
const int *subscripts, int32_t value)
{
- uint32_t magnitude;
- int sign;
-
- if (put_bits_left(pbc) < width + 1)
+ if (put_bits_left(pbc) < width)
return AVERROR(ENOSPC);
- sign = value < 0;
- magnitude = sign ? -value : value;
-
if (ctx->trace_enable) {
char bits[33];
int i;
for (i = 0; i < width; i++)
- bits[i] = magnitude >> (width - i - 1) & 1 ? '1' : '0';
- bits[i] = sign ? '1' : '0';
- bits[i + 1] = 0;
+ bits[i] = value & (1 << (width - i - 1)) ? '1' : '0';
+ bits[i] = 0;
ff_cbs_trace_syntax_element(ctx, put_bits_count(pbc),
name, subscripts, bits, value);
}
- put_bits(pbc, width, magnitude);
- put_bits(pbc, 1, sign);
+ put_sbits(pbc, width, value);
return 0;
}
--
1.9.1
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