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FFmpeg/libavcodec/g2meet.c
Michael Niedermayer e07ac727c1 avcodec/g2meet: Fix framebuf size
Currently the code can in some cases draw tiles that hang outside the
allocated buffer. This patch increases the buffer size to avoid out
of array accesses. An alternative would be to fail if such tiles are
encountered.
I do not know if any valid files use such hanging tiles.

Fixes Ticket2971
Found-by: ami_stuff
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2013-09-22 00:04:39 +02:00

870 lines
27 KiB
C

/*
* Go2Webinar decoder
* Copyright (c) 2012 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Go2Webinar decoder
*/
#include <zlib.h>
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "bytestream.h"
#include "dsputil.h"
#include "get_bits.h"
#include "internal.h"
#include "mjpeg.h"
enum ChunkType {
FRAME_INFO = 0xC8,
TILE_DATA,
CURSOR_POS,
CURSOR_SHAPE,
CHUNK_CC,
CHUNK_CD
};
enum Compression {
COMPR_EPIC_J_B = 2,
COMPR_KEMPF_J_B,
};
static const uint8_t luma_quant[64] = {
8, 6, 5, 8, 12, 20, 26, 31,
6, 6, 7, 10, 13, 29, 30, 28,
7, 7, 8, 12, 20, 29, 35, 28,
7, 9, 11, 15, 26, 44, 40, 31,
9, 11, 19, 28, 34, 55, 52, 39,
12, 18, 28, 32, 41, 52, 57, 46,
25, 32, 39, 44, 52, 61, 60, 51,
36, 46, 48, 49, 56, 50, 52, 50
};
static const uint8_t chroma_quant[64] = {
9, 9, 12, 24, 50, 50, 50, 50,
9, 11, 13, 33, 50, 50, 50, 50,
12, 13, 28, 50, 50, 50, 50, 50,
24, 33, 50, 50, 50, 50, 50, 50,
50, 50, 50, 50, 50, 50, 50, 50,
50, 50, 50, 50, 50, 50, 50, 50,
50, 50, 50, 50, 50, 50, 50, 50,
50, 50, 50, 50, 50, 50, 50, 50,
};
typedef struct JPGContext {
DSPContext dsp;
ScanTable scantable;
VLC dc_vlc[2], ac_vlc[2];
int prev_dc[3];
DECLARE_ALIGNED(16, int16_t, block)[6][64];
uint8_t *buf;
} JPGContext;
typedef struct G2MContext {
JPGContext jc;
int version;
int compression;
int width, height, bpp;
int tile_width, tile_height;
int tiles_x, tiles_y, tile_x, tile_y;
int got_header;
uint8_t *framebuf;
int framebuf_stride, old_width, old_height;
uint8_t *synth_tile, *jpeg_tile;
int tile_stride, old_tile_w, old_tile_h;
uint8_t *kempf_buf, *kempf_flags;
uint8_t *cursor;
int cursor_stride;
int cursor_fmt;
int cursor_w, cursor_h, cursor_x, cursor_y;
int cursor_hot_x, cursor_hot_y;
} G2MContext;
static av_cold int build_vlc(VLC *vlc, const uint8_t *bits_table,
const uint8_t *val_table, int nb_codes,
int is_ac)
{
uint8_t huff_size[256] = { 0 };
uint16_t huff_code[256];
uint16_t huff_sym[256];
int i;
ff_mjpeg_build_huffman_codes(huff_size, huff_code, bits_table, val_table);
for (i = 0; i < 256; i++)
huff_sym[i] = i + 16 * is_ac;
if (is_ac)
huff_sym[0] = 16 * 256;
return ff_init_vlc_sparse(vlc, 9, nb_codes, huff_size, 1, 1,
huff_code, 2, 2, huff_sym, 2, 2, 0);
}
static av_cold int jpg_init(AVCodecContext *avctx, JPGContext *c)
{
int ret;
ret = build_vlc(&c->dc_vlc[0], avpriv_mjpeg_bits_dc_luminance,
avpriv_mjpeg_val_dc, 12, 0);
if (ret)
return ret;
ret = build_vlc(&c->dc_vlc[1], avpriv_mjpeg_bits_dc_chrominance,
avpriv_mjpeg_val_dc, 12, 0);
if (ret)
return ret;
ret = build_vlc(&c->ac_vlc[0], avpriv_mjpeg_bits_ac_luminance,
avpriv_mjpeg_val_ac_luminance, 251, 1);
if (ret)
return ret;
ret = build_vlc(&c->ac_vlc[1], avpriv_mjpeg_bits_ac_chrominance,
avpriv_mjpeg_val_ac_chrominance, 251, 1);
if (ret)
return ret;
ff_dsputil_init(&c->dsp, avctx);
ff_init_scantable(c->dsp.idct_permutation, &c->scantable,
ff_zigzag_direct);
return 0;
}
static av_cold void jpg_free_context(JPGContext *ctx)
{
int i;
for (i = 0; i < 2; i++) {
ff_free_vlc(&ctx->dc_vlc[i]);
ff_free_vlc(&ctx->ac_vlc[i]);
}
av_freep(&ctx->buf);
}
static void jpg_unescape(const uint8_t *src, int src_size,
uint8_t *dst, int *dst_size)
{
const uint8_t *src_end = src + src_size;
uint8_t *dst_start = dst;
while (src < src_end) {
uint8_t x = *src++;
*dst++ = x;
if (x == 0xFF && !*src)
src++;
}
*dst_size = dst - dst_start;
}
static int jpg_decode_block(JPGContext *c, GetBitContext *gb,
int plane, int16_t *block)
{
int dc, val, pos;
const int is_chroma = !!plane;
const uint8_t *qmat = is_chroma ? chroma_quant : luma_quant;
c->dsp.clear_block(block);
dc = get_vlc2(gb, c->dc_vlc[is_chroma].table, 9, 3);
if (dc < 0)
return AVERROR_INVALIDDATA;
if (dc)
dc = get_xbits(gb, dc);
dc = dc * qmat[0] + c->prev_dc[plane];
block[0] = dc;
c->prev_dc[plane] = dc;
pos = 0;
while (pos < 63) {
val = get_vlc2(gb, c->ac_vlc[is_chroma].table, 9, 3);
if (val < 0)
return AVERROR_INVALIDDATA;
pos += val >> 4;
val &= 0xF;
if (pos > 63)
return val ? AVERROR_INVALIDDATA : 0;
if (val) {
int nbits = val;
val = get_xbits(gb, nbits);
val *= qmat[ff_zigzag_direct[pos]];
block[c->scantable.permutated[pos]] = val;
}
}
return 0;
}
static inline void yuv2rgb(uint8_t *out, int Y, int U, int V)
{
out[0] = av_clip_uint8(Y + ( 91881 * V + 32768 >> 16));
out[1] = av_clip_uint8(Y + (-22554 * U - 46802 * V + 32768 >> 16));
out[2] = av_clip_uint8(Y + (116130 * U + 32768 >> 16));
}
static int jpg_decode_data(JPGContext *c, int width, int height,
const uint8_t *src, int src_size,
uint8_t *dst, int dst_stride,
const uint8_t *mask, int mask_stride, int num_mbs,
int swapuv)
{
GetBitContext gb;
uint8_t *tmp;
int mb_w, mb_h, mb_x, mb_y, i, j;
int bx, by;
int unesc_size;
int ret;
tmp = av_realloc(c->buf, src_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!tmp)
return AVERROR(ENOMEM);
c->buf = tmp;
jpg_unescape(src, src_size, c->buf, &unesc_size);
memset(c->buf + unesc_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
init_get_bits(&gb, c->buf, unesc_size * 8);
width = FFALIGN(width, 16);
mb_w = width >> 4;
mb_h = (height + 15) >> 4;
if (!num_mbs)
num_mbs = mb_w * mb_h;
for (i = 0; i < 3; i++)
c->prev_dc[i] = 1024;
bx = by = 0;
for (mb_y = 0; mb_y < mb_h; mb_y++) {
for (mb_x = 0; mb_x < mb_w; mb_x++) {
if (mask && !mask[mb_x]) {
bx += 16;
continue;
}
for (j = 0; j < 2; j++) {
for (i = 0; i < 2; i++) {
if ((ret = jpg_decode_block(c, &gb, 0,
c->block[i + j * 2])) != 0)
return ret;
c->dsp.idct(c->block[i + j * 2]);
}
}
for (i = 1; i < 3; i++) {
if ((ret = jpg_decode_block(c, &gb, i, c->block[i + 3])) != 0)
return ret;
c->dsp.idct(c->block[i + 3]);
}
for (j = 0; j < 16; j++) {
uint8_t *out = dst + bx * 3 + (by + j) * dst_stride;
for (i = 0; i < 16; i++) {
int Y, U, V;
Y = c->block[(j >> 3) * 2 + (i >> 3)][(i & 7) + (j & 7) * 8];
U = c->block[4 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128;
V = c->block[5 ^ swapuv][(i >> 1) + (j >> 1) * 8] - 128;
yuv2rgb(out + i * 3, Y, U, V);
}
}
if (!--num_mbs)
return 0;
bx += 16;
}
bx = 0;
by += 16;
if (mask)
mask += mask_stride;
}
return 0;
}
static void kempf_restore_buf(const uint8_t *src, int len,
uint8_t *dst, int stride,
const uint8_t *jpeg_tile, int tile_stride,
int width, int height,
const uint8_t *pal, int npal, int tidx)
{
GetBitContext gb;
int i, j, nb, col;
init_get_bits(&gb, src, len * 8);
if (npal <= 2) nb = 1;
else if (npal <= 4) nb = 2;
else if (npal <= 16) nb = 4;
else nb = 8;
for (j = 0; j < height; j++, dst += stride, jpeg_tile += tile_stride) {
if (get_bits(&gb, 8))
continue;
for (i = 0; i < width; i++) {
col = get_bits(&gb, nb);
if (col != tidx)
memcpy(dst + i * 3, pal + col * 3, 3);
else
memcpy(dst + i * 3, jpeg_tile + i * 3, 3);
}
}
}
static int kempf_decode_tile(G2MContext *c, int tile_x, int tile_y,
const uint8_t *src, int src_size)
{
int width, height;
int hdr, zsize, npal, tidx = -1, ret;
int i, j;
const uint8_t *src_end = src + src_size;
uint8_t pal[768], transp[3];
uLongf dlen = (c->tile_width + 1) * c->tile_height;
int sub_type;
int nblocks, cblocks, bstride;
int bits, bitbuf, coded;
uint8_t *dst = c->framebuf + tile_x * c->tile_width * 3 +
tile_y * c->tile_height * c->framebuf_stride;
if (src_size < 2)
return AVERROR_INVALIDDATA;
width = FFMIN(c->width - tile_x * c->tile_width, c->tile_width);
height = FFMIN(c->height - tile_y * c->tile_height, c->tile_height);
hdr = *src++;
sub_type = hdr >> 5;
if (sub_type == 0) {
int j;
memcpy(transp, src, 3);
src += 3;
for (j = 0; j < height; j++, dst += c->framebuf_stride)
for (i = 0; i < width; i++)
memcpy(dst + i * 3, transp, 3);
return 0;
} else if (sub_type == 1) {
return jpg_decode_data(&c->jc, width, height, src, src_end - src,
dst, c->framebuf_stride, NULL, 0, 0, 0);
}
if (sub_type != 2) {
memcpy(transp, src, 3);
src += 3;
}
npal = *src++ + 1;
memcpy(pal, src, npal * 3); src += npal * 3;
if (sub_type != 2) {
for (i = 0; i < npal; i++) {
if (!memcmp(pal + i * 3, transp, 3)) {
tidx = i;
break;
}
}
}
if (src_end - src < 2)
return 0;
zsize = (src[0] << 8) | src[1]; src += 2;
if (src_end - src < zsize + (sub_type != 2))
return AVERROR_INVALIDDATA;
ret = uncompress(c->kempf_buf, &dlen, src, zsize);
if (ret)
return AVERROR_INVALIDDATA;
src += zsize;
if (sub_type == 2) {
kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride,
NULL, 0, width, height, pal, npal, tidx);
return 0;
}
nblocks = *src++ + 1;
cblocks = 0;
bstride = FFALIGN(width, 16) >> 4;
// blocks are coded LSB and we need normal bitreader for JPEG data
bits = 0;
for (i = 0; i < (FFALIGN(height, 16) >> 4); i++) {
for (j = 0; j < (FFALIGN(width, 16) >> 4); j++) {
if (!bits) {
if (src >= src_end)
return AVERROR_INVALIDDATA;
bitbuf = *src++;
bits = 8;
}
coded = bitbuf & 1;
bits--;
bitbuf >>= 1;
cblocks += coded;
if (cblocks > nblocks)
return AVERROR_INVALIDDATA;
c->kempf_flags[j + i * bstride] = coded;
}
}
memset(c->jpeg_tile, 0, c->tile_stride * height);
jpg_decode_data(&c->jc, width, height, src, src_end - src,
c->jpeg_tile, c->tile_stride,
c->kempf_flags, bstride, nblocks, 0);
kempf_restore_buf(c->kempf_buf, dlen, dst, c->framebuf_stride,
c->jpeg_tile, c->tile_stride,
width, height, pal, npal, tidx);
return 0;
}
static int g2m_init_buffers(G2MContext *c)
{
int aligned_height;
if (!c->framebuf || c->old_width < c->width || c->old_height < c->height) {
c->framebuf_stride = FFALIGN(c->width + 15, 16) * 3;
aligned_height = c->height + 15;
av_free(c->framebuf);
c->framebuf = av_mallocz(c->framebuf_stride * aligned_height);
if (!c->framebuf)
return AVERROR(ENOMEM);
}
if (!c->synth_tile || !c->jpeg_tile ||
c->old_tile_w < c->tile_width ||
c->old_tile_h < c->tile_height) {
c->tile_stride = FFALIGN(c->tile_width, 16) * 3;
aligned_height = FFALIGN(c->tile_height, 16);
av_free(c->synth_tile);
av_free(c->jpeg_tile);
av_free(c->kempf_buf);
av_free(c->kempf_flags);
c->synth_tile = av_mallocz(c->tile_stride * aligned_height);
c->jpeg_tile = av_mallocz(c->tile_stride * aligned_height);
c->kempf_buf = av_mallocz((c->tile_width + 1) * aligned_height
+ FF_INPUT_BUFFER_PADDING_SIZE);
c->kempf_flags = av_mallocz( c->tile_width * aligned_height);
if (!c->synth_tile || !c->jpeg_tile ||
!c->kempf_buf || !c->kempf_flags)
return AVERROR(ENOMEM);
}
return 0;
}
static int g2m_load_cursor(AVCodecContext *avctx, G2MContext *c,
GetByteContext *gb)
{
int i, j, k;
uint8_t *dst;
uint32_t bits;
uint32_t cur_size, cursor_w, cursor_h, cursor_stride;
uint32_t cursor_hot_x, cursor_hot_y;
int cursor_fmt;
uint8_t *tmp;
cur_size = bytestream2_get_be32(gb);
cursor_w = bytestream2_get_byte(gb);
cursor_h = bytestream2_get_byte(gb);
cursor_hot_x = bytestream2_get_byte(gb);
cursor_hot_y = bytestream2_get_byte(gb);
cursor_fmt = bytestream2_get_byte(gb);
cursor_stride = FFALIGN(cursor_w, 32) * 4;
if (cursor_w < 1 || cursor_w > 256 ||
cursor_h < 1 || cursor_h > 256) {
av_log(avctx, AV_LOG_ERROR, "Invalid cursor dimensions %dx%d\n",
cursor_w, cursor_h);
return AVERROR_INVALIDDATA;
}
if (cursor_hot_x > cursor_w || cursor_hot_y > cursor_h) {
av_log(avctx, AV_LOG_WARNING, "Invalid hotspot position %d,%d\n",
cursor_hot_x, cursor_hot_y);
cursor_hot_x = FFMIN(cursor_hot_x, cursor_w - 1);
cursor_hot_y = FFMIN(cursor_hot_y, cursor_h - 1);
}
if (cur_size - 9 > bytestream2_get_bytes_left(gb) ||
c->cursor_w * c->cursor_h / 4 > cur_size) {
av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %d/%d\n",
cur_size, bytestream2_get_bytes_left(gb));
return AVERROR_INVALIDDATA;
}
if (cursor_fmt != 1 && cursor_fmt != 32) {
avpriv_report_missing_feature(avctx, "Cursor format %d",
cursor_fmt);
return AVERROR_PATCHWELCOME;
}
tmp = av_realloc(c->cursor, cursor_stride * cursor_h);
if (!tmp) {
av_log(avctx, AV_LOG_ERROR, "Cannot allocate cursor buffer\n");
return AVERROR(ENOMEM);
}
c->cursor = tmp;
c->cursor_w = cursor_w;
c->cursor_h = cursor_h;
c->cursor_hot_x = cursor_hot_x;
c->cursor_hot_y = cursor_hot_y;
c->cursor_fmt = cursor_fmt;
c->cursor_stride = cursor_stride;
dst = c->cursor;
switch (c->cursor_fmt) {
case 1: // old monochrome
for (j = 0; j < c->cursor_h; j++) {
for (i = 0; i < c->cursor_w; i += 32) {
bits = bytestream2_get_be32(gb);
for (k = 0; k < 32; k++) {
dst[0] = !!(bits & 0x80000000);
dst += 4;
bits <<= 1;
}
}
}
dst = c->cursor;
for (j = 0; j < c->cursor_h; j++) {
for (i = 0; i < c->cursor_w; i += 32) {
bits = bytestream2_get_be32(gb);
for (k = 0; k < 32; k++) {
int mask_bit = !!(bits & 0x80000000);
switch (dst[0] * 2 + mask_bit) {
case 0:
dst[0] = 0xFF; dst[1] = 0x00;
dst[2] = 0x00; dst[3] = 0x00;
break;
case 1:
dst[0] = 0xFF; dst[1] = 0xFF;
dst[2] = 0xFF; dst[3] = 0xFF;
break;
default:
dst[0] = 0x00; dst[1] = 0x00;
dst[2] = 0x00; dst[3] = 0x00;
}
dst += 4;
bits <<= 1;
}
}
}
break;
case 32: // full colour
/* skip monochrome version of the cursor and decode RGBA instead */
bytestream2_skip(gb, c->cursor_h * (FFALIGN(c->cursor_w, 32) >> 3));
for (j = 0; j < c->cursor_h; j++) {
for (i = 0; i < c->cursor_w; i++) {
int val = bytestream2_get_be32(gb);
*dst++ = val >> 0;
*dst++ = val >> 8;
*dst++ = val >> 16;
*dst++ = val >> 24;
}
}
break;
default:
return AVERROR_PATCHWELCOME;
}
return 0;
}
#define APPLY_ALPHA(src, new, alpha) \
src = (src * (256 - alpha) + new * alpha) >> 8
static void g2m_paint_cursor(G2MContext *c, uint8_t *dst, int stride)
{
int i, j;
int x, y, w, h;
const uint8_t *cursor;
if (!c->cursor)
return;
x = c->cursor_x - c->cursor_hot_x;
y = c->cursor_y - c->cursor_hot_y;
cursor = c->cursor;
w = c->cursor_w;
h = c->cursor_h;
if (x + w > c->width)
w = c->width - x;
if (y + h > c->height)
h = c->height - y;
if (x < 0) {
w += x;
cursor += -x * 4;
} else {
dst += x * 3;
}
if (y < 0) {
h += y;
cursor += -y * c->cursor_stride;
} else {
dst += y * stride;
}
if (w < 0 || h < 0)
return;
for (j = 0; j < h; j++) {
for (i = 0; i < w; i++) {
uint8_t alpha = cursor[i * 4];
APPLY_ALPHA(dst[i * 3 + 0], cursor[i * 4 + 1], alpha);
APPLY_ALPHA(dst[i * 3 + 1], cursor[i * 4 + 2], alpha);
APPLY_ALPHA(dst[i * 3 + 2], cursor[i * 4 + 3], alpha);
}
dst += stride;
cursor += c->cursor_stride;
}
}
static int g2m_decode_frame(AVCodecContext *avctx, void *data,
int *got_picture_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
G2MContext *c = avctx->priv_data;
AVFrame *pic = data;
GetByteContext bc, tbc;
int magic;
int got_header = 0;
uint32_t chunk_size;
int chunk_type;
int i;
int ret;
if (buf_size < 12) {
av_log(avctx, AV_LOG_ERROR,
"Frame should have at least 12 bytes, got %d instead\n",
buf_size);
return AVERROR_INVALIDDATA;
}
bytestream2_init(&bc, buf, buf_size);
magic = bytestream2_get_be32(&bc);
if ((magic & ~0xF) != MKBETAG('G', '2', 'M', '0') ||
(magic & 0xF) < 2 || (magic & 0xF) > 4) {
av_log(avctx, AV_LOG_ERROR, "Wrong magic %08X\n", magic);
return AVERROR_INVALIDDATA;
}
if ((magic & 0xF) != 4) {
av_log(avctx, AV_LOG_ERROR, "G2M2 and G2M3 are not yet supported\n");
return AVERROR(ENOSYS);
}
while (bytestream2_get_bytes_left(&bc) > 5) {
chunk_size = bytestream2_get_le32(&bc) - 1;
chunk_type = bytestream2_get_byte(&bc);
if (chunk_size > bytestream2_get_bytes_left(&bc)) {
av_log(avctx, AV_LOG_ERROR, "Invalid chunk size %d type %02X\n",
chunk_size, chunk_type);
break;
}
switch (chunk_type) {
case FRAME_INFO:
c->got_header = 0;
if (chunk_size < 21) {
av_log(avctx, AV_LOG_ERROR, "Invalid frame info size %d\n",
chunk_size);
break;
}
c->width = bytestream2_get_be32(&bc);
c->height = bytestream2_get_be32(&bc);
if (c->width < 16 || c->width > avctx->width ||
c->height < 16 || c->height > avctx->height) {
av_log(avctx, AV_LOG_ERROR,
"Invalid frame dimensions %dx%d\n",
c->width, c->height);
ret = AVERROR_INVALIDDATA;
goto header_fail;
}
if (c->width != avctx->width || c->height != avctx->height)
avcodec_set_dimensions(avctx, c->width, c->height);
c->compression = bytestream2_get_be32(&bc);
if (c->compression != 2 && c->compression != 3) {
av_log(avctx, AV_LOG_ERROR,
"Unknown compression method %d\n",
c->compression);
return AVERROR_PATCHWELCOME;
}
c->tile_width = bytestream2_get_be32(&bc);
c->tile_height = bytestream2_get_be32(&bc);
if (!c->tile_width || !c->tile_height) {
av_log(avctx, AV_LOG_ERROR,
"Invalid tile dimensions %dx%d\n",
c->tile_width, c->tile_height);
ret = AVERROR_INVALIDDATA;
goto header_fail;
}
c->tiles_x = (c->width + c->tile_width - 1) / c->tile_width;
c->tiles_y = (c->height + c->tile_height - 1) / c->tile_height;
c->bpp = bytestream2_get_byte(&bc);
chunk_size -= 21;
bytestream2_skip(&bc, chunk_size);
if (g2m_init_buffers(c)) {
ret = AVERROR(ENOMEM);
goto header_fail;
}
got_header = 1;
break;
case TILE_DATA:
if (!c->tiles_x || !c->tiles_y) {
av_log(avctx, AV_LOG_WARNING,
"No frame header - skipping tile\n");
bytestream2_skip(&bc, bytestream2_get_bytes_left(&bc));
break;
}
if (chunk_size < 2) {
av_log(avctx, AV_LOG_ERROR, "Invalid tile data size %d\n",
chunk_size);
break;
}
c->tile_x = bytestream2_get_byte(&bc);
c->tile_y = bytestream2_get_byte(&bc);
if (c->tile_x >= c->tiles_x || c->tile_y >= c->tiles_y) {
av_log(avctx, AV_LOG_ERROR,
"Invalid tile pos %d,%d (in %dx%d grid)\n",
c->tile_x, c->tile_y, c->tiles_x, c->tiles_y);
break;
}
chunk_size -= 2;
ret = 0;
switch (c->compression) {
case COMPR_EPIC_J_B:
av_log(avctx, AV_LOG_ERROR,
"ePIC j-b compression is not implemented yet\n");
return AVERROR(ENOSYS);
case COMPR_KEMPF_J_B:
ret = kempf_decode_tile(c, c->tile_x, c->tile_y,
buf + bytestream2_tell(&bc),
chunk_size);
break;
}
if (ret && c->framebuf)
av_log(avctx, AV_LOG_ERROR, "Error decoding tile %d,%d\n",
c->tile_x, c->tile_y);
bytestream2_skip(&bc, chunk_size);
break;
case CURSOR_POS:
if (chunk_size < 5) {
av_log(avctx, AV_LOG_ERROR, "Invalid cursor pos size %d\n",
chunk_size);
break;
}
c->cursor_x = bytestream2_get_be16(&bc);
c->cursor_y = bytestream2_get_be16(&bc);
bytestream2_skip(&bc, chunk_size - 4);
break;
case CURSOR_SHAPE:
if (chunk_size < 8) {
av_log(avctx, AV_LOG_ERROR, "Invalid cursor data size %d\n",
chunk_size);
break;
}
bytestream2_init(&tbc, buf + bytestream2_tell(&bc),
chunk_size - 4);
g2m_load_cursor(avctx, c, &tbc);
bytestream2_skip(&bc, chunk_size);
break;
case CHUNK_CC:
case CHUNK_CD:
bytestream2_skip(&bc, chunk_size);
break;
default:
av_log(avctx, AV_LOG_WARNING, "Skipping chunk type %02X\n",
chunk_type);
bytestream2_skip(&bc, chunk_size);
}
}
if (got_header)
c->got_header = 1;
if (c->width && c->height && c->framebuf) {
if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
return ret;
pic->key_frame = got_header;
pic->pict_type = got_header ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
for (i = 0; i < avctx->height; i++)
memcpy(pic->data[0] + i * pic->linesize[0],
c->framebuf + i * c->framebuf_stride,
c->width * 3);
g2m_paint_cursor(c, pic->data[0], pic->linesize[0]);
*got_picture_ptr = 1;
}
return buf_size;
header_fail:
c->width = c->height = 0;
c->tiles_x = c->tiles_y = 0;
return ret;
}
static av_cold int g2m_decode_init(AVCodecContext *avctx)
{
G2MContext * const c = avctx->priv_data;
int ret;
if ((ret = jpg_init(avctx, &c->jc)) != 0) {
av_log(avctx, AV_LOG_ERROR, "Cannot initialise VLCs\n");
jpg_free_context(&c->jc);
return AVERROR(ENOMEM);
}
avctx->pix_fmt = AV_PIX_FMT_RGB24;
return 0;
}
static av_cold int g2m_decode_end(AVCodecContext *avctx)
{
G2MContext * const c = avctx->priv_data;
jpg_free_context(&c->jc);
av_freep(&c->kempf_buf);
av_freep(&c->kempf_flags);
av_freep(&c->synth_tile);
av_freep(&c->jpeg_tile);
av_freep(&c->cursor);
av_freep(&c->framebuf);
return 0;
}
AVCodec ff_g2m_decoder = {
.name = "g2m",
.long_name = NULL_IF_CONFIG_SMALL("Go2Meeting"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_G2M,
.priv_data_size = sizeof(G2MContext),
.init = g2m_decode_init,
.close = g2m_decode_end,
.decode = g2m_decode_frame,
.capabilities = CODEC_CAP_DR1,
};