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algmm: convert to bytestream2 API.

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Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
This commit is contained in:
Ronald S. Bultje 2012-03-06 15:15:42 -08:00
parent 8ca6e523a6
commit a55d5bdc6e
1 changed files with 51 additions and 38 deletions
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89
libavcodec/mmvideo.c
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@ -33,6 +33,7 @@
#include "libavutil/intreadwrite.h" #include "libavutil/intreadwrite.h"
#include "avcodec.h" #include "avcodec.h"
#include "bytestream.h"
#define MM_PREAMBLE_SIZE 6 #define MM_PREAMBLE_SIZE 6
@ -48,6 +49,7 @@ typedef struct MmContext {
AVCodecContext *avctx; AVCodecContext *avctx;
AVFrame frame; AVFrame frame;
int palette[AVPALETTE_COUNT]; int palette[AVPALETTE_COUNT];
GetByteContext gb;
} MmContext; } MmContext;
static av_cold int mm_decode_init(AVCodecContext *avctx) static av_cold int mm_decode_init(AVCodecContext *avctx)
@ -63,40 +65,40 @@ static av_cold int mm_decode_init(AVCodecContext *avctx)
return 0; return 0;
} }
static void mm_decode_pal(MmContext *s, const uint8_t *buf, const uint8_t *buf_end) static int mm_decode_pal(MmContext *s)
{ {
int i; int i;
buf += 4;
for (i=0; i<128 && buf+2<buf_end; i++) { bytestream2_skip(&s->gb, 4);
s->palette[i] = AV_RB24(buf); for (i = 0; i < 128; i++) {
s->palette[i] = bytestream2_get_be24(&s->gb);
s->palette[i+128] = s->palette[i]<<2; s->palette[i+128] = s->palette[i]<<2;
buf += 3;
} }
return 0;
} }
/** /**
* @param half_horiz Half horizontal resolution (0 or 1) * @param half_horiz Half horizontal resolution (0 or 1)
* @param half_vert Half vertical resolution (0 or 1) * @param half_vert Half vertical resolution (0 or 1)
*/ */
static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size) static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert)
{ {
int i, x, y; int i, x, y;
i=0; x=0; y=0; i=0; x=0; y=0;
while(i<buf_size) { while (bytestream2_get_bytes_left(&s->gb) > 0) {
int run_length, color; int run_length, color;
if (y >= s->avctx->height) if (y >= s->avctx->height)
return; return 0;
if (buf[i] & 0x80) { color = bytestream2_get_byte(&s->gb);
if (color & 0x80) {
run_length = 1; run_length = 1;
color = buf[i];
i++;
}else{ }else{
run_length = (buf[i] & 0x7f) + 2; run_length = (color & 0x7f) + 2;
color = buf[i+1]; color = bytestream2_get_byte(&s->gb);
i+=2;
} }
if (half_horiz) if (half_horiz)
@ -114,23 +116,28 @@ static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const
y += 1 + half_vert; y += 1 + half_vert;
} }
} }
return 0;
} }
/* /*
* @param half_horiz Half horizontal resolution (0 or 1) * @param half_horiz Half horizontal resolution (0 or 1)
* @param half_vert Half vertical resolution (0 or 1) * @param half_vert Half vertical resolution (0 or 1)
*/ */
static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size) static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert)
{ {
const int data_ptr = 2 + AV_RL16(&buf[0]); int data_off = bytestream2_get_le16(&s->gb), y;
int d, r, y; GetByteContext data_ptr;
d = data_ptr; r = 2; y = 0;
while(r < data_ptr) { if (bytestream2_get_bytes_left(&s->gb) < data_off)
return AVERROR_INVALIDDATA;
bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off);
while (s->gb.buffer < data_ptr.buffer_start) {
int i, j; int i, j;
int length = buf[r] & 0x7f; int length = bytestream2_get_byte(&s->gb);
int x = buf[r+1] + ((buf[r] & 0x80) << 1); int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1);
r += 2; length &= 0x7F;
if (length==0) { if (length==0) {
y += x; y += x;
@ -138,13 +145,14 @@ static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const
} }
if (y + half_vert >= s->avctx->height) if (y + half_vert >= s->avctx->height)
return; return 0;
for(i=0; i<length; i++) { for(i=0; i<length; i++) {
int replace_array = bytestream2_get_byte(&s->gb);
for(j=0; j<8; j++) { for(j=0; j<8; j++) {
int replace = (buf[r+i] >> (7-j)) & 1; int replace = (replace_array >> (7-j)) & 1;
if (replace) { if (replace) {
int color = buf[d]; int color = bytestream2_get_byte(&data_ptr);
s->frame.data[0][y*s->frame.linesize[0] + x] = color; s->frame.data[0][y*s->frame.linesize[0] + x] = color;
if (half_horiz) if (half_horiz)
s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color; s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color;
@ -153,15 +161,15 @@ static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const
if (half_horiz) if (half_horiz)
s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color; s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color;
} }
d++;
} }
x += 1 + half_horiz; x += 1 + half_horiz;
} }
} }
r += length;
y += 1 + half_vert; y += 1 + half_vert;
} }
return 0;
} }
static int mm_decode_frame(AVCodecContext *avctx, static int mm_decode_frame(AVCodecContext *avctx,
@ -171,12 +179,14 @@ static int mm_decode_frame(AVCodecContext *avctx,
const uint8_t *buf = avpkt->data; const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size; int buf_size = avpkt->size;
MmContext *s = avctx->priv_data; MmContext *s = avctx->priv_data;
const uint8_t *buf_end = buf+buf_size; int type, res;
int type;
if (buf_size < MM_PREAMBLE_SIZE)
return AVERROR_INVALIDDATA;
type = AV_RL16(&buf[0]); type = AV_RL16(&buf[0]);
buf += MM_PREAMBLE_SIZE; buf += MM_PREAMBLE_SIZE;
buf_size -= MM_PREAMBLE_SIZE; buf_size -= MM_PREAMBLE_SIZE;
bytestream2_init(&s->gb, buf, buf_size);
if (avctx->reget_buffer(avctx, &s->frame) < 0) { if (avctx->reget_buffer(avctx, &s->frame) < 0) {
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
@ -184,16 +194,19 @@ static int mm_decode_frame(AVCodecContext *avctx,
} }
switch(type) { switch(type) {
case MM_TYPE_PALETTE : mm_decode_pal(s, buf, buf_end); return buf_size; case MM_TYPE_PALETTE : res = mm_decode_pal(s); return buf_size;
case MM_TYPE_INTRA : mm_decode_intra(s, 0, 0, buf, buf_size); break; case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break;
case MM_TYPE_INTRA_HH : mm_decode_intra(s, 1, 0, buf, buf_size); break; case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break;
case MM_TYPE_INTRA_HHV : mm_decode_intra(s, 1, 1, buf, buf_size); break; case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break;
case MM_TYPE_INTER : mm_decode_inter(s, 0, 0, buf, buf_size); break; case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break;
case MM_TYPE_INTER_HH : mm_decode_inter(s, 1, 0, buf, buf_size); break; case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break;
case MM_TYPE_INTER_HHV : mm_decode_inter(s, 1, 1, buf, buf_size); break; case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break;
default : default:
return -1; res = AVERROR_INVALIDDATA;
break;
} }
if (res < 0)
return res;
memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);