* 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 "bitstream.h"
+#include "internal.h"
+#include "mathops.h"
-typedef struct WNV1Context{
+typedef struct WNV1Context {
AVCodecContext *avctx;
- AVFrame pic;
int shift;
- /* bit buffer */
- unsigned long bitbuf;
- int bits;
- uint8_t *buf;
+ BitstreamContext bc;
} 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 = bitstream_read_vlc(&w->bc, 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[bitstream_read(&w->bc, 8 - w->shift)];
+ else
+ return base_value + ((v - 7) << w->shift);
}
-static int decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- uint8_t *buf, int buf_size)
+static int decode_frame(AVCodecContext *avctx,
+ void *data, int *got_frame,
+ AVPacket *avpkt)
{
WNV1Context * const l = avctx->priv_data;
- AVFrame * const p= (AVFrame*)&l->pic;
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ AVFrame * const p = data;
unsigned char *Y,*U,*V;
- int i, j;
+ int i, j, ret;
int prev_y = 0, prev_u = 0, prev_v = 0;
+ uint8_t *rbuf;
+
+ if (buf_size < 8) {
+ av_log(avctx, AV_LOG_ERROR, "Packet is too short\n");
+ return AVERROR_INVALIDDATA;
+ }
- if(p->data[0])
- avctx->release_buffer(avctx, p);
+ rbuf = av_malloc(buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!rbuf) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
+ return AVERROR(ENOMEM);
+ }
- p->reference = 0;
- if(avctx->get_buffer(avctx, p) < 0){
+ if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
- return -1;
+ av_free(rbuf);
+ return ret;
}
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]];
+ bitstream_init(&l->bc, 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);
+ avpriv_request_sample(avctx,
+ "Unknown WNV1 frame header value %i",
+ 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);
+ avpriv_request_sample(avctx,
+ "Unknown WNV1 frame header value %i",
+ 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;
-
+
+ *got_frame = 1;
+ 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 = AV_PIX_FMT_YUV422P;
- l->avctx = avctx;
- avctx->pix_fmt = 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;
}
-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",
+ .long_name = NULL_IF_CONFIG_SMALL("Winnov WNV1"),
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_WNV1,
+ .priv_data_size = sizeof(WNV1Context),
+ .init = decode_init,
+ .decode = decode_frame,
+ .capabilities = AV_CODEC_CAP_DR1,
};
projects / ffmpeg / blobdiff