Binary text decoder

Decoder and demuxer for various binary text formats.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 252 insertions, 0 deletions

diff --git a/libavcodec/bintext.c b/libavcodec/bintext.c
new file mode 100644
index 0000000000..0726d4689d
--- /dev/null
+++ b/libavcodec/bintext.c
@@ -0,0 +1,252 @@
+/*
+ * Binary text decoder
+ * eXtended BINary text (XBIN) decoder
+ * iCEDraw File decoder
+ * Copyright (c) 2010 Peter Ross (pross@xvid.org)
+ *
+ * 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 libavcodec/xbin.c
+ * Binary text decoder
+ * eXtended BINary text (XBIN) decoder
+ * iCEDraw File decoder
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "avcodec.h"
+#include "cga_data.h"
+#include "bintext.h"
+
+typedef struct XbinContext {
+    AVFrame frame;
+    int palette[16];
+    int flags;
+    int font_height;
+    const uint8_t *font;
+    int x, y;
+} XbinContext;
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+    XbinContext *s = avctx->priv_data;
+    uint8_t *p;
+    int i;
+
+    avctx->pix_fmt = PIX_FMT_PAL8;
+    s->frame.reference = 1;
+    if (avctx->get_buffer(avctx, &s->frame)) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return -1;
+    }
+
+    p = avctx->extradata;
+    if (p) {
+        s->font_height = p[0];
+        s->flags = p[1];
+        p += 2;
+    } else {
+        s->font_height = 8;
+        s->flags = 0;
+    }
+
+    if ((s->flags & BINTEXT_PALETTE)) {
+        for (i = 0; i < 16; i++) {
+            s->palette[i] = 0xFF000000 | (AV_RB24(p) << 2);
+            p += 3;
+        }
+    } else {
+        for (i = 0; i < 16; i++)
+            s->palette[i] = 0xFF000000 | ff_cga_palette[i];
+    }
+
+    if ((s->flags & BINTEXT_FONT)) {
+        s->font = p;
+    } else {
+        switch(s->font_height) {
+        default:
+            av_log(avctx, AV_LOG_WARNING, "font height %i not support\n", s->font_height);
+            s->font_height = 8;
+        case 8:
+            s->font = ff_cga_font;
+            break;
+        case 16:
+            s->font = ff_vga16_font;
+            break;
+        }
+    }
+
+    return 0;
+}
+
+#define DEFAULT_BG_COLOR 0
+static void hscroll(AVCodecContext *avctx)
+{
+    XbinContext *s = avctx->priv_data;
+    if (s->y < avctx->height - s->font_height) {
+        s->y += s->font_height;
+    } else {
+        memmove(s->frame.data[0], s->frame.data[0] + s->font_height*s->frame.linesize[0],
+            (avctx->height - s->font_height)*s->frame.linesize[0]);
+        memset(s->frame.data[0] + (avctx->height - s->font_height)*s->frame.linesize[0],
+            DEFAULT_BG_COLOR, s->font_height * s->frame.linesize[0]);
+    }
+}
+
+#define FONT_WIDTH 8
+
+/**
+ * Draw character to screen
+ */
+static void draw_char(AVCodecContext *avctx, int c, int a)
+{
+    XbinContext *s = avctx->priv_data;
+    if (s->y > avctx->height - s->font_height)
+        return;
+    ff_draw_pc_font(s->frame.data[0] + s->y * s->frame.linesize[0] + s->x,
+                    s->frame.linesize[0], s->font, s->font_height, c,
+                    a & 0x0F, a >> 4);
+    s->x += FONT_WIDTH;
+    if (s->x >= avctx->width) {
+        s->x = 0;
+        s->y += s->font_height;
+    }
+}
+
+static int decode_frame(AVCodecContext *avctx,
+                            void *data, int *data_size,
+                            AVPacket *avpkt)
+{
+    XbinContext *s = avctx->priv_data;
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
+    const uint8_t *buf_end = buf+buf_size;
+
+    if (avctx->reget_buffer(avctx, &s->frame)) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return -1;
+    }
+    s->frame.pict_type           = FF_I_TYPE;
+    s->frame.palette_has_changed = 1;
+    memcpy(s->frame.data[1], s->palette, 16 * 4);
+
+    if (avctx->codec_id == CODEC_ID_XBIN) {
+        while (buf + 2 < buf_end) {
+            int i,c,a;
+            int type  = *buf >> 6;
+            int count = (*buf & 0x3F) + 1;
+            buf++;
+            switch (type) {
+            case 0: //no compression
+                for (i = 0; i < count && buf + 1 < buf_end; i++) {
+                    draw_char(avctx, buf[0], buf[1]);
+                    buf += 2;
+                }
+                break;
+            case 1: //character compression
+                c = *buf++;
+                for (i = 0; i < count && buf < buf_end; i++)
+                    draw_char(avctx, c, *buf++);
+                break;
+            case 2: //attribute compression
+                a = *buf++;
+                for (i = 0; i < count && buf < buf_end; i++)
+                    draw_char(avctx, *buf++, a);
+                break;
+            case 3: //character/attribute compression
+                c = *buf++;
+                a = *buf++;
+                for (i = 0; i < count && buf < buf_end; i++)
+                    draw_char(avctx, c, a);
+                break;
+            }
+        }
+    } else if (avctx->codec_id == CODEC_ID_IDF) {
+        while (buf + 2 < buf_end) {
+            if (AV_RL16(buf) == 1) {
+               int i;
+               if (buf + 6 > buf_end)
+                   break;
+               for (i = 0; i < buf[2]; i++)
+                   draw_char(avctx, buf[4], buf[5]);
+               buf += 6;
+            } else {
+               draw_char(avctx, buf[0], buf[1]);
+               buf += 2;
+            }
+        }
+    } else {
+        while (buf + 1 < buf_end) {
+            draw_char(avctx, buf[0], buf[1]);
+            buf += 2;
+        }
+    }
+
+    *data_size = sizeof(AVFrame);
+    *(AVFrame*)data = s->frame;
+    return buf_size;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx)
+{
+    XbinContext *s = avctx->priv_data;
+
+    if (s->frame.data[0])
+        avctx->release_buffer(avctx, &s->frame);
+
+    return 0;
+}
+
+AVCodec ff_bintext_decoder = {
+    "xbin",
+    AVMEDIA_TYPE_VIDEO,
+    CODEC_ID_BINTEXT,
+    sizeof(XbinContext),
+    decode_init,
+    NULL,
+    decode_end,
+    decode_frame,
+    CODEC_CAP_DR1,
+    .long_name = NULL_IF_CONFIG_SMALL("Binary text"),
+};
+
+AVCodec ff_xbin_decoder = {
+    "xbin",
+    AVMEDIA_TYPE_VIDEO,
+    CODEC_ID_XBIN,
+    sizeof(XbinContext),
+    decode_init,
+    NULL,
+    decode_end,
+    decode_frame,
+    CODEC_CAP_DR1,
+    .long_name = NULL_IF_CONFIG_SMALL("eXtended BINary text"),
+};
+
+AVCodec ff_idf_decoder = {
+    "idf",
+    AVMEDIA_TYPE_VIDEO,
+    CODEC_ID_IDF,
+    sizeof(XbinContext),
+    decode_init,
+    NULL,
+    decode_end,
+    decode_frame,
+    CODEC_CAP_DR1,
+    .long_name = NULL_IF_CONFIG_SMALL("iCEDraw text"),
+};