int ff_cbs_read_unsigned(CodedBitstreamContext *ctx, BitstreamContext *bc,
int width, const char *name, uint32_t *write_to,
uint32_t range_min, uint32_t range_max)
{
uint32_t value;
int position;
av_assert0(width <= 32);
if (bitstream_bits_left(bc) < width) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid value at "
"%s: bitstream ended.\n", name);
return AVERROR_INVALIDDATA;
}
if (ctx->trace_enable)
position = bitstream_tell(bc);
value = bitstream_read(bc, width);
if (ctx->trace_enable) {
char bits[33];
int i;
for (i = 0; i < width; i++)
bits[i] = value >> (width - i - 1) & 1 ? '1' : '0';
bits[i] = 0;
ff_cbs_trace_syntax_element(ctx, position, name, bits, value);
}
static int find_group3_syncmarker(BitstreamContext *bc, int srcsize)
{
unsigned int state = -1;
srcsize -= bitstream_tell(bc);
while (srcsize-- > 0) {
state += state + bitstream_read_bit(bc);
if ((state & 0xFFF) == 1)
return 0;
}
return -1;
}
static int cbs_read_se_golomb(CodedBitstreamContext *ctx, BitstreamContext *bc,
const char *name, int32_t *write_to,
int32_t range_min, int32_t range_max)
{
int32_t value;
int position, i, j;
unsigned int k;
uint32_t v;
char bits[65];
position = bitstream_tell(bc);
for (i = 0; i < 32; i++) {
if (bitstream_bits_left(bc) < i + 1) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
"%s: bitstream ended.\n", name);
return AVERROR_INVALIDDATA;
}
k = bitstream_read_bit(bc);
bits[i] = k ? '1' : '0';
if (k)
break;
}
if (i >= 32) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid se-golomb code at "
"%s: more than 31 zeroes.\n", name);
return AVERROR_INVALIDDATA;
}
v = 1;
for (j = 0; j < i; j++) {
k = bitstream_read_bit(bc);
bits[i + j + 1] = k ? '1' : '0';
v = v << 1 | k;
}
bits[i + j + 1] = 0;
if (v & 1)
value = -(int32_t)(v / 2);
else
value = v / 2;
if (ctx->trace_enable)
ff_cbs_trace_syntax_element(ctx, position, name, bits, value);
if (value < range_min || value > range_max) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "%s out of range: "
"%"PRId32", but must be in [%"PRId32",%"PRId32"].\n",
name, value, range_min, range_max);
return AVERROR_INVALIDDATA;
}
*write_to = value;
return 0;
}
static void get_bits_align32(BitstreamContext *s)
{
int n = (-bitstream_tell(s)) & 31;
if (n)
bitstream_skip(s, n);
}
