add V.Flash PTX decoder

Originally committed as revision 8856 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ptx.c

@@ -0,0 +1,119 @@
+/*
+ * V.Flash PTX (.ptx) image decoder
+ * Copyright (c) 2007 Ivo van Poorten
+ *
+ * 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
+ *
+ */
+
+#include "avcodec.h"
+
+typedef struct PTXContext {
+    AVFrame picture;
+} PTXContext;
+
+static int ptx_init(AVCodecContext *avctx) {
+    PTXContext *s = avctx->priv_data;
+
+    avcodec_get_frame_defaults((AVFrame*)&s->picture);
+    avctx->coded_frame= (AVFrame*)&s->picture;
+    s->picture.data[0] = NULL;
+
+    return 0;
+}
+
+static int ptx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
+                            uint8_t *buf, int buf_size) {
+    PTXContext * const s = avctx->priv_data;
+    AVFrame *picture = data;
+    AVFrame * const p = (AVFrame *)&s->picture;
+    unsigned int offset, w, h, y, stride, bytes_per_pixel;
+    uint8_t *ptr;
+
+    offset          = AV_RL16(buf);
+    w               = AV_RL16(buf+8);
+    h               = AV_RL16(buf+10);
+    bytes_per_pixel = AV_RL16(buf+12) >> 3;
+
+    if (bytes_per_pixel != 2) {
+        av_log(avctx, AV_LOG_ERROR, "image format is not rgb15, please report on ffmpeg-users mailing list\n");
+        return -1;
+    }
+
+    avctx->pix_fmt = PIX_FMT_RGB555;
+
+    if (offset != 0x2c)
+        av_log(avctx, AV_LOG_WARNING, "offset != 0x2c, untested due to lack of sample files\n");
+
+    buf += offset;
+
+    if (p->data[0])
+        avctx->release_buffer(avctx, p);
+
+    if (avcodec_check_dimensions(avctx, w, h))
+        return -1;
+    if (w != avctx->width || h != avctx->height)
+        avcodec_set_dimensions(avctx, w, h);
+    if (avctx->get_buffer(avctx, p) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return -1;
+    }
+
+    p->pict_type = FF_I_TYPE;
+
+    ptr    = p->data[0];
+    stride = p->linesize[0];
+
+    for (y=0; y<h; y++) {
+#ifdef WORDS_BIGENDIAN
+        unsigned int x;
+        for (x=0; x<w*bytes_per_pixel; x+=bytes_per_pixel)
+            ST16(ptr+x, AV_RL16(buf+x));
+#else
+        memcpy(ptr, buf, w*bytes_per_pixel);
+#endif
+        ptr += stride;
+        buf += w*bytes_per_pixel;
+    }
+
+    *picture = *(AVFrame *)&s->picture;
+    *data_size = sizeof(AVPicture);
+
+    return offset + w*h*bytes_per_pixel;
+}
+
+static int ptx_end(AVCodecContext *avctx) {
+    PTXContext *s = avctx->priv_data;
+
+    if(s->picture.data[0])
+        avctx->release_buffer(avctx, &s->picture);
+
+    return 0;
+}
+
+AVCodec ptx_decoder = {
+    "ptx",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_PTX,
+    sizeof(PTXContext),
+    ptx_init,
+    NULL,
+    ptx_end,
+    ptx_decode_frame,
+    0,
+    NULL
+};