virtualenv/FFmpeg
1
0
Fork 0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
Code Issues Releases Activity

avcodec/roqvideodec: Move transient GetByteContext to the stack

Browse Source 
This avoids keeping potentially dangling pointers in the context,
beautifies the code (by replacing "&ri->gb" by gb for every access to
the GetByteContext) and also highlights the GetByteContext's short-lived
nature better.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2020-08-30 14:06:11 +02:00
parent 72942ad6d4
commit a067d44955
2 changed files with 31 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
libavcodec/roqvideo.h
View File

@ -52,7 +52,6 @@ typedef struct RoqContext {
roq_cell cb2x2[256];
roq_qcell cb4x4[256];
GetByteContext gb;
int width, height;
/* Encoder only data */

61
libavcodec/roqvideodec.c
View File

@ -33,7 +33,7 @@
#include "internal.h"
#include "roqvideo.h"
static void roqvideo_decode_frame(RoqContext *ri)
static void roqvideo_decode_frame(RoqContext *ri, GetByteContext *gb)
{
unsigned int chunk_id = 0, chunk_arg = 0;
unsigned long chunk_size = 0;
@ -43,10 +43,10 @@ static void roqvideo_decode_frame(RoqContext *ri)
roq_qcell *qcell;
int64_t chunk_start;
while (bytestream2_get_bytes_left(&ri->gb) >= 8) {
chunk_id = bytestream2_get_le16(&ri->gb);
chunk_size = bytestream2_get_le32(&ri->gb);
chunk_arg = bytestream2_get_le16(&ri->gb);
while (bytestream2_get_bytes_left(gb) >= 8) {
chunk_id = bytestream2_get_le16(gb);
chunk_size = bytestream2_get_le32(gb);
chunk_arg = bytestream2_get_le16(gb);
if(chunk_id == RoQ_QUAD_VQ)
break;
@ -56,36 +56,36 @@ static void roqvideo_decode_frame(RoqContext *ri)
if((nv2 = chunk_arg & 0xff) == 0 && nv1 * 6 < chunk_size)
nv2 = 256;
for(i = 0; i < nv1; i++) {
ri->cb2x2[i].y[0] = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].y[1] = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].y[2] = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].y[3] = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].u = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].v = bytestream2_get_byte(&ri->gb);
ri->cb2x2[i].y[0] = bytestream2_get_byte(gb);
ri->cb2x2[i].y[1] = bytestream2_get_byte(gb);
ri->cb2x2[i].y[2] = bytestream2_get_byte(gb);
ri->cb2x2[i].y[3] = bytestream2_get_byte(gb);
ri->cb2x2[i].u = bytestream2_get_byte(gb);
ri->cb2x2[i].v = bytestream2_get_byte(gb);
}
for(i = 0; i < nv2; i++)
for(j = 0; j < 4; j++)
ri->cb4x4[i].idx[j] = bytestream2_get_byte(&ri->gb);
ri->cb4x4[i].idx[j] = bytestream2_get_byte(gb);
}
}
chunk_start = bytestream2_tell(&ri->gb);
chunk_start = bytestream2_tell(gb);
xpos = ypos = 0;
if (chunk_size > bytestream2_get_bytes_left(&ri->gb)) {
if (chunk_size > bytestream2_get_bytes_left(gb)) {
av_log(ri->avctx, AV_LOG_ERROR, "Chunk does not fit in input buffer\n");
chunk_size = bytestream2_get_bytes_left(&ri->gb);
chunk_size = bytestream2_get_bytes_left(gb);
}
while (bytestream2_tell(&ri->gb) < chunk_start + chunk_size) {
while (bytestream2_tell(gb) < chunk_start + chunk_size) {
for (yp = ypos; yp < ypos + 16; yp += 8)
for (xp = xpos; xp < xpos + 16; xp += 8) {
if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
if (bytestream2_tell(gb) >= chunk_start + chunk_size) {
av_log(ri->avctx, AV_LOG_VERBOSE, "Chunk is too short\n");
return;
}
if (vqflg_pos < 0) {
vqflg = bytestream2_get_le16(&ri->gb);
vqflg = bytestream2_get_le16(gb);
vqflg_pos = 7;
}
vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
@ -96,14 +96,14 @@ static void roqvideo_decode_frame(RoqContext *ri)
case RoQ_ID_MOT:
break;
case RoQ_ID_FCC: {
int byte = bytestream2_get_byte(&ri->gb);
int byte = bytestream2_get_byte(gb);
mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
ff_apply_motion_8x8(ri, xp, yp, mx, my);
break;
}
case RoQ_ID_SLD:
qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
qcell = ri->cb4x4 + bytestream2_get_byte(gb);
ff_apply_vector_4x4(ri, xp, yp, ri->cb2x2 + qcell->idx[0]);
ff_apply_vector_4x4(ri, xp + 4, yp, ri->cb2x2 + qcell->idx[1]);
ff_apply_vector_4x4(ri, xp, yp + 4, ri->cb2x2 + qcell->idx[2]);
@ -115,12 +115,12 @@ static void roqvideo_decode_frame(RoqContext *ri)
if(k & 0x01) x += 4;
if(k & 0x02) y += 4;
if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
if (bytestream2_tell(gb) >= chunk_start + chunk_size) {
av_log(ri->avctx, AV_LOG_VERBOSE, "Chunk is too short\n");
return;
}
if (vqflg_pos < 0) {
vqflg = bytestream2_get_le16(&ri->gb);
vqflg = bytestream2_get_le16(gb);
vqflg_pos = 7;
}
vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
@ -130,24 +130,24 @@ static void roqvideo_decode_frame(RoqContext *ri)
case RoQ_ID_MOT:
break;
case RoQ_ID_FCC: {
int byte = bytestream2_get_byte(&ri->gb);
int byte = bytestream2_get_byte(gb);
mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
ff_apply_motion_4x4(ri, x, y, mx, my);
break;
}
case RoQ_ID_SLD:
qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
qcell = ri->cb4x4 + bytestream2_get_byte(gb);
ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + qcell->idx[0]);
ff_apply_vector_2x2(ri, x + 2, y, ri->cb2x2 + qcell->idx[1]);
ff_apply_vector_2x2(ri, x, y + 2, ri->cb2x2 + qcell->idx[2]);
ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + qcell->idx[3]);
break;
case RoQ_ID_CCC:
ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
ff_apply_vector_2x2(ri, x + 2, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
ff_apply_vector_2x2(ri, x, y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + bytestream2_get_byte(gb));
ff_apply_vector_2x2(ri, x + 2, y, ri->cb2x2 + bytestream2_get_byte(gb));
ff_apply_vector_2x2(ri, x, y + 2, ri->cb2x2 + bytestream2_get_byte(gb));
ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + bytestream2_get_byte(gb));
break;
}
}
@ -201,6 +201,7 @@ static int roq_decode_frame(AVCodecContext *avctx,
int buf_size = avpkt->size;
RoqContext *s = avctx->priv_data;
int copy = !s->current_frame->data[0] && s->last_frame->data[0];
GetByteContext gb;
int ret;
if ((ret = ff_reget_buffer(avctx, s->current_frame, 0)) < 0)
@ -212,8 +213,8 @@ static int roq_decode_frame(AVCodecContext *avctx,
return ret;
}
bytestream2_init(&s->gb, buf, buf_size);
roqvideo_decode_frame(s);
bytestream2_init(&gb, buf, buf_size);
roqvideo_decode_frame(s, &gb);
if ((ret = av_frame_ref(data, s->current_frame)) < 0)
return ret;