* Winnov WNV1 codec
* Copyright (c) 2005 Konstantin Shishkov
*
- * This library is free software; you can redistribute it and/or
+ * This file is part of Libav.
+ *
+ * Libav 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
*
- * This library is distributed in the hope that it will be useful,
+ * Libav 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 this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-
+
/**
- * @file wnv1.c
+ * @file
* Winnov WNV1 codec.
*/
-
+
#include "avcodec.h"
-#include "common.h"
+#include "get_bits.h"
+#include "mathops.h"
typedef struct WNV1Context{
AVFrame pic;
int shift;
- /* bit buffer */
- unsigned long bitbuf;
- int bits;
- uint8_t *buf;
+ GetBitContext gb;
} WNV1Context;
+static const uint16_t code_tab[16][2]={
+{0x1FD,9}, {0xFD,8}, {0x7D,7}, {0x3D,6}, {0x1D,5}, {0x0D,4}, {0x005,3},
+{0x000,1},
+{0x004,3}, {0x0C,4}, {0x1C,5}, {0x3C,6}, {0x7C,7}, {0xFC,8}, {0x1FC,9}, {0xFF,8}
+};
+
+#define CODE_VLC_BITS 9
+static VLC code_vlc;
+
/* returns modified base_value */
static inline int wnv1_get_code(WNV1Context *w, int base_value)
{
- int v = 0;
-
- if (w->bits < 16) { /* need to fill bit buffer */
- w->bitbuf |= LE_16(w->buf) << w->bits;
- w->buf += 2;
- w->bits += 16;
- }
-
- /* escape code */
- if ((w->bitbuf & 0xFF) == 0xFF) {
- w->bitbuf >>= 8;
- w->bits -= 8;
- if (w->bits < 16) { /* need to fill bit buffer */
- w->bitbuf |= LE_16(w->buf) << w->bits;
- w->buf += 2;
- w->bits += 16;
- }
- v = w->bitbuf & (0xFF >> w->shift);
- w->bitbuf >>= 8 - w->shift;
- w->bits -= 8 - w->shift;
- return v << w->shift;
- }
+ int v = get_vlc2(&w->gb, code_vlc.table, CODE_VLC_BITS, 1);
- /* zero code */
- if (!(w->bitbuf & 1)) {
- w->bitbuf >>= 1;
- w->bits--;
- return base_value;
- }
-
- /* reversed unary code and sign */
- while (w->bits && w->bitbuf & 1) {
- w->bitbuf >>= 1;
- w->bits--;
- v++;
- }
- w->bitbuf >>= 1;
- w->bits--;
- if(w->bitbuf & 1)
- v = -v;
- w->bitbuf >>= 1;
- w->bits--;
- v <<= w->shift;
- return base_value + v;
+ if(v==15)
+ return ff_reverse[ get_bits(&w->gb, 8 - w->shift) ];
+ else
+ return base_value + ((v - 7)<<w->shift);
}
-static int decode_frame(AVCodecContext *avctx,
+static int decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
- uint8_t *buf, int buf_size)
+ AVPacket *avpkt)
{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
WNV1Context * const l = avctx->priv_data;
- AVFrame * const p= (AVFrame*)&l->pic;
+ AVFrame * const p = &l->pic;
unsigned char *Y,*U,*V;
int i, j;
int prev_y = 0, prev_u = 0, prev_v = 0;
+ uint8_t *rbuf;
+
+ rbuf = av_malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
+ if(!rbuf){
+ av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
+ return -1;
+ }
if(p->data[0])
avctx->release_buffer(avctx, p);
p->reference = 0;
if(avctx->get_buffer(avctx, p) < 0){
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ av_free(rbuf);
return -1;
}
p->key_frame = 1;
-
- l->bitbuf = 0;
- l->bits = 0;
- l->buf = buf + 8;
-
+
+ for(i=8; i<buf_size; i++)
+ rbuf[i]= ff_reverse[ buf[i] ];
+ init_get_bits(&l->gb, rbuf+8, (buf_size-8)*8);
+
if (buf[2] >> 4 == 6)
l->shift = 2;
else {
l->shift = 8 - (buf[2] >> 4);
if (l->shift > 4) {
- av_log(avctx, AV_LOG_ERROR, "Unknown WNV1 frame header value %i, please upload file for study\n", buf[2] >> 4);
+ av_log_ask_for_sample(avctx, "Unknown WNV1 frame header value %i\n",
+ buf[2] >> 4);
l->shift = 4;
}
if (l->shift < 1) {
- av_log(avctx, AV_LOG_ERROR, "Unknown WNV1 frame header value %i, please upload file for study\n", buf[2] >> 4);
+ av_log_ask_for_sample(avctx, "Unknown WNV1 frame header value %i\n",
+ buf[2] >> 4);
l->shift = 1;
}
}
-
+
Y = p->data[0];
U = p->data[1];
V = p->data[2];
V += p->linesize[2];
}
-
+
*data_size = sizeof(AVFrame);
*(AVFrame*)data = l->pic;
-
+ av_free(rbuf);
+
return buf_size;
}
-static int decode_init(AVCodecContext *avctx){
+static av_cold int decode_init(AVCodecContext *avctx){
WNV1Context * const l = avctx->priv_data;
+ static VLC_TYPE code_table[1 << CODE_VLC_BITS][2];
l->avctx = avctx;
- avctx->pix_fmt = PIX_FMT_YUV422P;
+ avctx->pix_fmt = AV_PIX_FMT_YUV422P;
+
+ code_vlc.table = code_table;
+ code_vlc.table_allocated = 1 << CODE_VLC_BITS;
+ init_vlc(&code_vlc, CODE_VLC_BITS, 16,
+ &code_tab[0][1], 4, 2,
+ &code_tab[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
+
+ return 0;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx){
+ WNV1Context * const l = avctx->priv_data;
+ AVFrame *pic = &l->pic;
+
+ if (pic->data[0])
+ avctx->release_buffer(avctx, pic);
return 0;
}
-AVCodec wnv1_decoder = {
- "wnv1",
- CODEC_TYPE_VIDEO,
- CODEC_ID_WNV1,
- sizeof(WNV1Context),
- decode_init,
- NULL,
- NULL,
- decode_frame,
- CODEC_CAP_DR1,
+AVCodec ff_wnv1_decoder = {
+ .name = "wnv1",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_WNV1,
+ .priv_data_size = sizeof(WNV1Context),
+ .init = decode_init,
+ .close = decode_end,
+ .decode = decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Winnov WNV1"),
};
projects / ffmpeg / blobdiff