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avcodec/smc: use shorter way to access GetByteContext

This commit is contained in:
Paul B Mahol 2021-08-14 10:15:40 +02:00
parent b6156dd665
commit f852490f72
1 changed files with 20 additions and 19 deletions
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39
libavcodec/smc.c
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@ -60,7 +60,7 @@ typedef struct SmcContext {
} SmcContext;
#define GET_BLOCK_COUNT() \
(opcode & 0x10) ? (1 + bytestream2_get_byte(&s->gb)) : 1 + (opcode & 0x0F);
(opcode & 0x10) ? (1 + bytestream2_get_byte(gb)) : 1 + (opcode & 0x0F);
#define ADVANCE_BLOCK() \
{ \
@ -80,12 +80,13 @@ typedef struct SmcContext {
static int smc_decode_stream(SmcContext *s)
{
GetByteContext *gb = &s->gb;
int width = s->avctx->width;
int height = s->avctx->height;
int stride = s->frame->linesize[0];
int i;
int chunk_size;
int buf_size = bytestream2_size(&s->gb);
int buf_size = bytestream2_size(gb);
uint8_t opcode;
int n_blocks;
unsigned int color_flags;
@ -115,8 +116,8 @@ static int smc_decode_stream(SmcContext *s)
/* make the palette available */
memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
bytestream2_skip(&s->gb, 1);
chunk_size = bytestream2_get_be24(&s->gb);
bytestream2_skip(gb, 1);
chunk_size = bytestream2_get_be24(gb);
if (chunk_size != buf_size)
av_log(s->avctx, AV_LOG_WARNING, "MOV chunk size != encoded chunk size (%d != %d); using MOV chunk size\n",
chunk_size, buf_size);
@ -133,12 +134,12 @@ static int smc_decode_stream(SmcContext *s)
row_ptr, image_size);
return AVERROR_INVALIDDATA;
}
if (bytestream2_get_bytes_left(&s->gb) < 1) {
if (bytestream2_get_bytes_left(gb) < 1) {
av_log(s->avctx, AV_LOG_ERROR, "input too small\n");
return AVERROR_INVALIDDATA;
}
opcode = bytestream2_get_byteu(&s->gb);
opcode = bytestream2_get_byteu(gb);
switch (opcode & 0xF0) {
/* skip n blocks */
case 0x00:
@ -233,7 +234,7 @@ static int smc_decode_stream(SmcContext *s)
case 0x60:
case 0x70:
n_blocks = GET_BLOCK_COUNT();
pixel = bytestream2_get_byte(&s->gb);
pixel = bytestream2_get_byte(gb);
while (n_blocks--) {
block_ptr = row_ptr + pixel_ptr;
@ -257,7 +258,7 @@ static int smc_decode_stream(SmcContext *s)
/* fetch the next 2 colors from bytestream and store in next
* available entry in the color pair table */
for (i = 0; i < CPAIR; i++) {
pixel = bytestream2_get_byte(&s->gb);
pixel = bytestream2_get_byte(gb);
color_table_index = CPAIR * color_pair_index + i;
s->color_pairs[color_table_index] = pixel;
}
@ -268,10 +269,10 @@ static int smc_decode_stream(SmcContext *s)
if (color_pair_index == COLORS_PER_TABLE)
color_pair_index = 0;
} else
color_table_index = CPAIR * bytestream2_get_byte(&s->gb);
color_table_index = CPAIR * bytestream2_get_byte(gb);
while (n_blocks--) {
color_flags = bytestream2_get_be16(&s->gb);
color_flags = bytestream2_get_be16(gb);
flag_mask = 0x8000;
block_ptr = row_ptr + pixel_ptr;
for (pixel_y = 0; pixel_y < 4; pixel_y++) {
@ -299,7 +300,7 @@ static int smc_decode_stream(SmcContext *s)
/* fetch the next 4 colors from bytestream and store in next
* available entry in the color quad table */
for (i = 0; i < CQUAD; i++) {
pixel = bytestream2_get_byte(&s->gb);
pixel = bytestream2_get_byte(gb);
color_table_index = CQUAD * color_quad_index + i;
s->color_quads[color_table_index] = pixel;
}
@ -310,10 +311,10 @@ static int smc_decode_stream(SmcContext *s)
if (color_quad_index == COLORS_PER_TABLE)
color_quad_index = 0;
} else
color_table_index = CQUAD * bytestream2_get_byte(&s->gb);
color_table_index = CQUAD * bytestream2_get_byte(gb);
while (n_blocks--) {
color_flags = bytestream2_get_be32(&s->gb);
color_flags = bytestream2_get_be32(gb);
/* flag mask actually acts as a bit shift count here */
flag_mask = 30;
block_ptr = row_ptr + pixel_ptr;
@ -340,7 +341,7 @@ static int smc_decode_stream(SmcContext *s)
/* fetch the next 8 colors from bytestream and store in next
* available entry in the color octet table */
for (i = 0; i < COCTET; i++) {
pixel = bytestream2_get_byte(&s->gb);
pixel = bytestream2_get_byte(gb);
color_table_index = COCTET * color_octet_index + i;
s->color_octets[color_table_index] = pixel;
}
@ -351,7 +352,7 @@ static int smc_decode_stream(SmcContext *s)
if (color_octet_index == COLORS_PER_TABLE)
color_octet_index = 0;
} else
color_table_index = COCTET * bytestream2_get_byte(&s->gb);
color_table_index = COCTET * bytestream2_get_byte(gb);
while (n_blocks--) {
/*
@ -361,9 +362,9 @@ static int smc_decode_stream(SmcContext *s)
flags_a = xx012456, flags_b = xx89A37B
*/
/* build the color flags */
int val1 = bytestream2_get_be16(&s->gb);
int val2 = bytestream2_get_be16(&s->gb);
int val3 = bytestream2_get_be16(&s->gb);
int val1 = bytestream2_get_be16(gb);
int val2 = bytestream2_get_be16(gb);
int val3 = bytestream2_get_be16(gb);
color_flags_a = ((val1 & 0xFFF0) << 8) | (val2 >> 4);
color_flags_b = ((val3 & 0xFFF0) << 8) |
((val1 & 0x0F) << 8) | ((val2 & 0x0F) << 4) | (val3 & 0x0F);
@ -399,7 +400,7 @@ static int smc_decode_stream(SmcContext *s)
block_ptr = row_ptr + pixel_ptr;
for (pixel_y = 0; pixel_y < 4; pixel_y++) {
for (pixel_x = 0; pixel_x < 4; pixel_x++) {
pixels[block_ptr++] = bytestream2_get_byte(&s->gb);
pixels[block_ptr++] = bytestream2_get_byte(gb);
}
block_ptr += row_inc;
}