pngenc: better upper bound for encoded frame size.

Fixes encoding very large pictures.

Thanks to Костя for providing the formula.
This commit is contained in:
Anton Khirnov 2012-03-21 09:48:26 +01:00
parent f036342b4b
commit 677df4d2ef
1 changed files with 17 additions and 13 deletions

View File

@ -235,7 +235,7 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
PNGEncContext *s = avctx->priv_data;
AVFrame * const p= &s->picture;
int bit_depth, color_type, y, len, row_size, ret, is_progressive;
int bits_per_pixel, pass_row_size, max_packet_size;
int bits_per_pixel, pass_row_size, enc_row_size, max_packet_size;
int compression_level;
uint8_t *ptr, *top;
uint8_t *crow_base = NULL, *crow_buf, *crow;
@ -247,18 +247,6 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
p->pict_type= AV_PICTURE_TYPE_I;
p->key_frame= 1;
max_packet_size = IOBUF_SIZE*avctx->height + FF_MIN_BUFFER_SIZE;
if (!pkt->data &&
(ret = av_new_packet(pkt, max_packet_size)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate output packet of size %d.\n",
max_packet_size);
return ret;
}
s->bytestream_start =
s->bytestream = pkt->data;
s->bytestream_end = pkt->data + pkt->size;
is_progressive = !!(avctx->flags & CODEC_FLAG_INTERLACED_DCT);
switch(avctx->pix_fmt) {
case PIX_FMT_RGB32:
@ -297,6 +285,22 @@ static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
Z_DEFLATED, 15, 8, Z_DEFAULT_STRATEGY);
if (ret != Z_OK)
return -1;
enc_row_size = deflateBound(&s->zstream, row_size);
max_packet_size = avctx->height * (enc_row_size +
((enc_row_size + IOBUF_SIZE - 1) / IOBUF_SIZE) * 12)
+ FF_MIN_BUFFER_SIZE;
if (!pkt->data &&
(ret = av_new_packet(pkt, max_packet_size)) < 0) {
av_log(avctx, AV_LOG_ERROR, "Could not allocate output packet of size %d.\n",
max_packet_size);
return ret;
}
s->bytestream_start =
s->bytestream = pkt->data;
s->bytestream_end = pkt->data + pkt->size;
crow_base = av_malloc((row_size + 32) << (s->filter_type == PNG_FILTER_VALUE_MIXED));
if (!crow_base)
goto fail;