* Winnov WNV1 codec.
*/
+#include "libavutil/thread.h"
+
+#define BITSTREAM_READER_LE
#include "avcodec.h"
#include "get_bits.h"
#include "internal.h"
-#include "mathops.h"
-
-
-typedef struct WNV1Context {
- int shift;
- 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 }
+static const uint8_t code_tab[16][2] = {
+ { 7, 1 }, { 8, 3 }, { 6, 3 }, { 9, 4 }, { 5, 4 }, { 10, 5 }, { 4, 5 },
+ { 11, 6 }, { 3, 6 }, { 12, 7 }, { 2, 7 }, { 13, 8 }, { 1, 8 }, { 14, 9 },
+ { 0, 9 }, { 15, 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)
+static inline int wnv1_get_code(GetBitContext *gb, int shift, int base_value)
{
- int v = get_vlc2(&w->gb, code_vlc.table, CODE_VLC_BITS, 1);
+ int v = get_vlc2(gb, code_vlc.table, CODE_VLC_BITS, 1);
- if (v == 15)
- return ff_reverse[get_bits(&w->gb, 8 - w->shift)];
+ if (v == 8)
+ return get_bits(gb, 8 - shift) << shift;
else
- return base_value + ((v - 7U) << w->shift);
+ return base_value + v * (1 << shift);
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
- WNV1Context * const l = avctx->priv_data;
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
AVFrame * const p = data;
+ GetBitContext gb;
unsigned char *Y,*U,*V;
- int i, j, ret;
+ int i, j, ret, shift;
int prev_y = 0, prev_u = 0, prev_v = 0;
- uint8_t *rbuf;
if (buf_size < 8 + avctx->height * (avctx->width/2)/8) {
av_log(avctx, AV_LOG_ERROR, "Packet size %d is too small\n", buf_size);
return AVERROR_INVALIDDATA;
}
- 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);
- }
- memset(rbuf + buf_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
-
- if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
- av_free(rbuf);
+ if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
return ret;
- }
p->key_frame = 1;
- for (i = 8; i < buf_size; i++)
- rbuf[i] = ff_reverse[buf[i]];
-
- if ((ret = init_get_bits8(&l->gb, rbuf + 8, buf_size - 8)) < 0)
+ if ((ret = init_get_bits8(&gb, buf + 8, buf_size - 8)) < 0)
return ret;
if (buf[2] >> 4 == 6)
- l->shift = 2;
+ shift = 2;
else {
- l->shift = 8 - (buf[2] >> 4);
- if (l->shift > 4) {
+ shift = 8 - (buf[2] >> 4);
+ if (shift > 4) {
avpriv_request_sample(avctx,
"Unknown WNV1 frame header value %i",
buf[2] >> 4);
- l->shift = 4;
+ shift = 4;
}
- if (l->shift < 1) {
+ if (shift < 1) {
avpriv_request_sample(avctx,
"Unknown WNV1 frame header value %i",
buf[2] >> 4);
- l->shift = 1;
+ shift = 1;
}
}
V = p->data[2];
for (j = 0; j < avctx->height; j++) {
for (i = 0; i < avctx->width / 2; i++) {
- Y[i * 2] = wnv1_get_code(l, prev_y);
- prev_u = U[i] = wnv1_get_code(l, prev_u);
- prev_y = Y[(i * 2) + 1] = wnv1_get_code(l, Y[i * 2]);
- prev_v = V[i] = wnv1_get_code(l, prev_v);
+ Y[i * 2] = wnv1_get_code(&gb, shift, prev_y);
+ prev_u = U[i] = wnv1_get_code(&gb, shift, prev_u);
+ prev_y = Y[(i * 2) + 1] = wnv1_get_code(&gb, shift, Y[i * 2]);
+ prev_v = V[i] = wnv1_get_code(&gb, shift, prev_v);
}
Y += p->linesize[0];
U += p->linesize[1];
*got_frame = 1;
- av_free(rbuf);
return buf_size;
}
+static av_cold void wnv1_init_static(void)
+{
+ INIT_VLC_STATIC_FROM_LENGTHS(&code_vlc, CODE_VLC_BITS, 16,
+ &code_tab[0][1], 2,
+ &code_tab[0][0], 2, 1,
+ -7, INIT_VLC_OUTPUT_LE, 1 << CODE_VLC_BITS);
+}
+
static av_cold int decode_init(AVCodecContext *avctx)
{
- static VLC_TYPE code_table[1 << CODE_VLC_BITS][2];
+ static AVOnce init_static_once = AV_ONCE_INIT;
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);
+ ff_thread_once(&init_static_once, wnv1_init_static);
return 0;
}
.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,
+ .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};