summaryrefslogtreecommitdiff
path: root/ffmpeg/libavcodec/wnv1.c
diff options
context:
space:
mode:
authorTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
committerTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
commit8992cb1d0d07edc33d274f6d7924ecdf6f83d994 (patch)
tree3a2c86846b7eec8137c1507e623fc7018f13d453 /ffmpeg/libavcodec/wnv1.c
parent741fb4b9e135cfb161a749db88713229038577bb (diff)
making act segmenter
Diffstat (limited to 'ffmpeg/libavcodec/wnv1.c')
-rw-r--r--ffmpeg/libavcodec/wnv1.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/wnv1.c b/ffmpeg/libavcodec/wnv1.c
new file mode 100644
index 0000000..162dd1f
--- /dev/null
+++ b/ffmpeg/libavcodec/wnv1.c
@@ -0,0 +1,160 @@
+/*
+ * Winnov WNV1 codec
+ * Copyright (c) 2005 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
+ * Winnov WNV1 codec.
+ */
+
+#include "avcodec.h"
+#include "get_bits.h"
+#include "internal.h"
+#include "mathops.h"
+
+
+typedef struct WNV1Context {
+ AVCodecContext *avctx;
+
+ 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 }
+};
+
+#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 = get_vlc2(&w->gb, code_vlc.table, CODE_VLC_BITS, 1);
+
+ 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,
+ 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;
+ unsigned char *Y,*U,*V;
+ 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, "buf_size %d is too small\n", buf_size);
+ return AVERROR_INVALIDDATA;
+ }
+
+ rbuf = av_malloc(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
+ if (!rbuf) {
+ av_log(avctx, AV_LOG_ERROR, "Cannot allocate temporary buffer\n");
+ return AVERROR(ENOMEM);
+ }
+
+ if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
+ av_free(rbuf);
+ return ret;
+ }
+ p->key_frame = 1;
+
+ 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) {
+ avpriv_request_sample(avctx,
+ "Unknown WNV1 frame header value %i",
+ buf[2] >> 4);
+ l->shift = 4;
+ }
+ if (l->shift < 1) {
+ 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];
+ 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 += p->linesize[0];
+ U += p->linesize[1];
+ V += p->linesize[2];
+ }
+
+
+ *got_frame = 1;
+ av_free(rbuf);
+
+ return buf_size;
+}
+
+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;
+
+ 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 ff_wnv1_decoder = {
+ .name = "wnv1",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_WNV1,
+ .priv_data_size = sizeof(WNV1Context),
+ .init = decode_init,
+ .decode = decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("Winnov WNV1"),
+};