ffmpeg-2.1.1: move directory

git-svn-id: svn://kolibrios.org@6148 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/ffmpeg/ffmpeg-2.1/libavcodec/mjpegbdec.c

@@ -0,0 +1,167 @@
+/*
+ * Apple MJPEG-B decoder
+ * Copyright (c) 2002 Alex Beregszaszi
+ *
+ * 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
+ * Apple MJPEG-B decoder.
+ */
+
+#include "avcodec.h"
+#include "mjpeg.h"
+#include "mjpegdec.h"
+
+static uint32_t read_offs(AVCodecContext *avctx, GetBitContext *gb, uint32_t size, const char *err_msg){
+    uint32_t offs= get_bits_long(gb, 32);
+    if(offs >= size){
+        av_log(avctx, AV_LOG_WARNING, err_msg, offs, size);
+        return 0;
+    }
+    return offs;
+}
+
+static int mjpegb_decode_frame(AVCodecContext *avctx,
+                              void *data, int *got_frame,
+                              AVPacket *avpkt)
+{
+    const uint8_t *buf = avpkt->data;
+    int buf_size = avpkt->size;
+    MJpegDecodeContext *s = avctx->priv_data;
+    const uint8_t *buf_end, *buf_ptr;
+    GetBitContext hgb; /* for the header */
+    uint32_t dqt_offs, dht_offs, sof_offs, sos_offs, second_field_offs;
+    uint32_t field_size, sod_offs;
+    int ret;
+
+    buf_ptr = buf;
+    buf_end = buf + buf_size;
+    s->got_picture = 0;
+
+read_header:
+    /* reset on every SOI */
+    s->restart_interval = 0;
+    s->restart_count = 0;
+    s->mjpb_skiptosod = 0;
+
+    if (buf_end - buf_ptr >= 1 << 28)
+        return AVERROR_INVALIDDATA;
+
+    init_get_bits(&hgb, buf_ptr, /*buf_size*/(buf_end - buf_ptr)*8);
+
+    skip_bits(&hgb, 32); /* reserved zeros */
+
+    if (get_bits_long(&hgb, 32) != MKBETAG('m','j','p','g'))
+    {
+        av_log(avctx, AV_LOG_WARNING, "not mjpeg-b (bad fourcc)\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    field_size = get_bits_long(&hgb, 32); /* field size */
+    av_log(avctx, AV_LOG_DEBUG, "field size: 0x%x\n", field_size);
+    skip_bits(&hgb, 32); /* padded field size */
+    second_field_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "second_field_offs is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "second field offs: 0x%x\n", second_field_offs);
+
+    dqt_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "dqt is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "dqt offs: 0x%x\n", dqt_offs);
+    if (dqt_offs)
+    {
+        init_get_bits(&s->gb, buf_ptr+dqt_offs, (buf_end - (buf_ptr+dqt_offs))*8);
+        s->start_code = DQT;
+        if (ff_mjpeg_decode_dqt(s) < 0 &&
+            (avctx->err_recognition & AV_EF_EXPLODE))
+          return AVERROR_INVALIDDATA;
+    }
+
+    dht_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "dht is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "dht offs: 0x%x\n", dht_offs);
+    if (dht_offs)
+    {
+        init_get_bits(&s->gb, buf_ptr+dht_offs, (buf_end - (buf_ptr+dht_offs))*8);
+        s->start_code = DHT;
+        ff_mjpeg_decode_dht(s);
+    }
+
+    sof_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "sof is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "sof offs: 0x%x\n", sof_offs);
+    if (sof_offs)
+    {
+        init_get_bits(&s->gb, buf_ptr+sof_offs, (buf_end - (buf_ptr+sof_offs))*8);
+        s->start_code = SOF0;
+        if (ff_mjpeg_decode_sof(s) < 0)
+            return -1;
+    }
+
+    sos_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "sos is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "sos offs: 0x%x\n", sos_offs);
+    sod_offs = read_offs(avctx, &hgb, buf_end - buf_ptr, "sof is %d and size is %d\n");
+    av_log(avctx, AV_LOG_DEBUG, "sod offs: 0x%x\n", sod_offs);
+    if (sos_offs)
+    {
+        init_get_bits(&s->gb, buf_ptr + sos_offs,
+                      8 * FFMIN(field_size, buf_end - buf_ptr - sos_offs));
+        s->mjpb_skiptosod = (sod_offs - sos_offs - show_bits(&s->gb, 16));
+        s->start_code = SOS;
+        if (ff_mjpeg_decode_sos(s, NULL, NULL) < 0 &&
+            (avctx->err_recognition & AV_EF_EXPLODE))
+          return AVERROR_INVALIDDATA;
+    }
+
+    if (s->interlaced) {
+        s->bottom_field ^= 1;
+        /* if not bottom field, do not output image yet */
+        if (s->bottom_field != s->interlace_polarity && second_field_offs)
+        {
+            buf_ptr = buf + second_field_offs;
+            goto read_header;
+            }
+    }
+
+    //XXX FIXME factorize, this looks very similar to the EOI code
+
+    if(!s->got_picture) {
+        av_log(avctx, AV_LOG_WARNING, "no picture\n");
+        return buf_size;
+    }
+
+    if ((ret = av_frame_ref(data, s->picture_ptr)) < 0)
+        return ret;
+    *got_frame = 1;
+
+    if (!s->lossless && avctx->debug & FF_DEBUG_QP) {
+        av_log(avctx, AV_LOG_DEBUG, "QP: %d\n",
+               FFMAX3(s->qscale[0], s->qscale[1], s->qscale[2]));
+    }
+
+    return buf_size;
+}
+
+AVCodec ff_mjpegb_decoder = {
+    .name           = "mjpegb",
+    .long_name      = NULL_IF_CONFIG_SMALL("Apple MJPEG-B"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_MJPEGB,
+    .priv_data_size = sizeof(MJpegDecodeContext),
+    .init           = ff_mjpeg_decode_init,
+    .close          = ff_mjpeg_decode_end,
+    .decode         = mjpegb_decode_frame,
+    .capabilities   = CODEC_CAP_DR1,
+    .max_lowres     = 3,
+};