Add ICO muxer

Signed-off-by: Michael Bradshaw <mbradshaw@sorensonmedia.com>
Reviewed-by: Peter Ross <pross@xvid.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Changelog

@@ -45,6 +45,7 @@ version next:
 - smptebars source
 - asetpts filter
 - hue filter
+- ICO muxer
 
 
 version 0.11:

doc/general.texi

@@ -212,7 +212,7 @@ library:
     @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley
          playout servers.
 @item iCEDraw File              @tab   @tab X
-@item ICO                       @tab   @tab X
+@item ICO                       @tab X @tab X
     @tab Microsoft Windows ICO
 @item id Quake II CIN video     @tab   @tab X
 @item id RoQ                    @tab X @tab X

doc/muxers.texi

@@ -129,6 +129,39 @@ ffmpeg -i INPUT -f framemd5 -
 
 See also the @ref{md5} muxer.
 
+@anchor{ico}
+@section ico
+
+ICO file muxer.
+
+Microsoft's icon file format (ICO) has some strict limitations that should be noted:
+
+@itemize
+@item
+Size cannot exceed 256 pixels in any dimension
+
+@item
+Only BMP and PNG images can be stored
+
+@item
+If a BMP image is used, it must be one of the following pixel formats:
+@example
+BMP Bit Depth      FFmpeg Pixel Format
+1bit               pal8
+4bit               pal8
+8bit               pal8
+16bit              rgb555le
+24bit              bgr24
+32bit              bgra
+@end example
+
+@item
+If a BMP image is used, it must use the BITMAPINFOHEADER DIB header
+
+@item
+If a PNG image is used, it must use the rgba pixel format
+@end itemize
+
 @anchor{image2}
 @section image2
 

libavformat/Makefile

@@ -122,6 +122,7 @@ OBJS-$(CONFIG_H264_DEMUXER)              += h264dec.o rawdec.o
 OBJS-$(CONFIG_H264_MUXER)                += rawenc.o
 OBJS-$(CONFIG_HLS_DEMUXER)               += hls.o
 OBJS-$(CONFIG_ICO_DEMUXER)               += icodec.o
+OBJS-$(CONFIG_ICO_MUXER)                 += icoenc.o
 OBJS-$(CONFIG_IDCIN_DEMUXER)             += idcin.o
 OBJS-$(CONFIG_IDF_DEMUXER)               += bintext.o
 OBJS-$(CONFIG_IFF_DEMUXER)               += iff.o

libavformat/allformats.c

@@ -112,7 +112,7 @@ void av_register_all(void)
     REGISTER_MUXDEMUX (H263, h263);
     REGISTER_MUXDEMUX (H264, h264);
     REGISTER_DEMUXER  (HLS, hls);
-    REGISTER_DEMUXER  (ICO, ico);
+    REGISTER_MUXDEMUX (ICO, ico);
     REGISTER_DEMUXER  (IDCIN, idcin);
     REGISTER_DEMUXER  (IDF, idf);
     REGISTER_DEMUXER  (IFF, iff);

libavformat/icoenc.c

@@ -0,0 +1,204 @@
+/*
+ * Microsoft Windows ICO muxer
+ * Copyright (c) 2012 Michael Bradshaw <mbradshaw@sorensonmedia.com>
+ *
+ * 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
+ * Microsoft Windows ICO muxer
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "libavutil/pixdesc.h"
+#include "avformat.h"
+
+typedef struct {
+    int offset;
+    int size;
+    unsigned char width;
+    unsigned char height;
+    short bits;
+} IcoImage;
+
+typedef struct {
+    int current_image;
+    int nb_images;
+    IcoImage *images;
+} IcoMuxContext;
+
+static int ico_check_attributes(AVFormatContext *s, const AVCodecContext *c)
+{
+    if (c->codec_id == CODEC_ID_BMP) {
+        if (c->pix_fmt == PIX_FMT_PAL8 && PIX_FMT_RGB32 != PIX_FMT_BGRA) {
+            av_log(s, AV_LOG_ERROR, "Wrong endianness for bmp pixel format\n");
+            return AVERROR(EINVAL);
+        } else if (c->pix_fmt != PIX_FMT_PAL8 &&
+                   c->pix_fmt != PIX_FMT_RGB555LE &&
+                   c->pix_fmt != PIX_FMT_BGR24 &&
+                   c->pix_fmt != PIX_FMT_BGRA) {
+            av_log(s, AV_LOG_ERROR, "BMP must be 1bit, 4bit, 8bit, 16bit, 24bit, or 32bit\n");
+            return AVERROR(EINVAL);
+        }
+    } else if (c->codec_id == CODEC_ID_PNG) {
+        if (c->pix_fmt != PIX_FMT_RGBA) {
+            av_log(s, AV_LOG_ERROR, "PNG in ico requires pixel format to be rgba\n");
+            return AVERROR(EINVAL);
+        }
+    } else {
+        av_log(s, AV_LOG_ERROR, "Unsupported codec %s\n", c->codec_name);
+        return AVERROR(EINVAL);
+    }
+
+    if (c->width > 256 ||
+        c->height > 256) {
+        av_log(s, AV_LOG_ERROR, "Unsupported dimensions %dx%d (dimensions cannot exceed 256x256)\n", c->width, c->height);
+        return AVERROR(EINVAL);
+    }
+
+    return 0;
+}
+
+static int ico_write_header(AVFormatContext *s)
+{
+    IcoMuxContext *ico = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int ret;
+    int i;
+
+    if (!pb->seekable) {
+        av_log(s, AV_LOG_ERROR, "Output is not seekable\n");
+        return AVERROR(EINVAL);
+    }
+
+    ico->current_image = 0;
+    ico->nb_images = s->nb_streams;
+
+    avio_wl16(pb, 0); // reserved
+    avio_wl16(pb, 1); // 1 == icon
+    avio_skip(pb, 2); // skip the number of images
+
+    for (i = 0; i < s->nb_streams; i++) {
+        if (ret = ico_check_attributes(s, s->streams[i]->codec))
+            return ret;
+
+        // Fill in later when writing trailer...
+        avio_skip(pb, 16);
+    }
+
+    ico->images = av_mallocz(ico->nb_images * sizeof(IcoMuxContext));
+    if (!ico->images)
+        return AVERROR(ENOMEM);
+
+    avio_flush(pb);
+
+    return 0;
+}
+
+static int ico_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    IcoMuxContext *ico = s->priv_data;
+    IcoImage *image;
+    AVIOContext *pb = s->pb;
+    AVCodecContext *c = s->streams[pkt->stream_index]->codec;
+    int i;
+
+    if (ico->current_image >= ico->nb_images) {
+        av_log(s, AV_LOG_ERROR, "ICO already contains %d images\n", ico->current_image);
+        return AVERROR(EIO);
+    }
+
+    image = &ico->images[ico->current_image++];
+
+    image->offset = avio_tell(pb);
+    image->width = (c->width == 256) ? 0 : c->width;
+    image->height = (c->height == 256) ? 0 : c->height;
+
+    if (c->codec_id == CODEC_ID_PNG) {
+        image->bits = c->bits_per_coded_sample;
+        image->size = pkt->size;
+
+        avio_write(pb, pkt->data, pkt->size);
+    } else { // BMP
+        if (AV_RL32(pkt->data + 14) != 40) { // must be BITMAPINFOHEADER
+            av_log(s, AV_LOG_ERROR, "Invalid BMP\n");
+            return AVERROR(EINVAL);
+        }
+
+        image->bits = AV_RL16(pkt->data + 28); // allows things like 1bit and 4bit images to be preserved
+        image->size = pkt->size - 14 + c->height * (c->width + 7) / 8;
+
+        avio_write(pb, pkt->data + 14, 8); // Skip the BITMAPFILEHEADER header
+        avio_wl32(pb, AV_RL32(pkt->data + 22) * 2); // rewrite height as 2 * height
+        avio_write(pb, pkt->data + 26, pkt->size - 26);
+
+        for (i = 0; i < c->height * (c->width + 7) / 8; ++i)
+            avio_w8(pb, 0x00); // Write bitmask (opaque)
+    }
+
+    avio_flush(pb);
+
+    return 0;
+}
+
+static int ico_write_trailer(AVFormatContext *s)
+{
+    IcoMuxContext *ico = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int i;
+
+    avio_seek(pb, 4, SEEK_SET);
+
+    avio_wl16(pb, ico->current_image);
+
+    for (i = 0; i < ico->nb_images; i++) {
+        avio_w8(pb, ico->images[i].width);
+        avio_w8(pb, ico->images[i].height);
+
+        if (s->streams[i]->codec->codec_id == CODEC_ID_BMP &&
+            s->streams[i]->codec->pix_fmt == PIX_FMT_PAL8) {
+            avio_w8(pb, (ico->images[i].bits >= 8) ? 0 : 1 << ico->images[i].bits);
+        } else {
+            avio_w8(pb, 0);
+        }
+
+        avio_w8(pb, 0); // reserved
+        avio_wl16(pb, 1); // color planes
+        avio_wl16(pb, ico->images[i].bits);
+        avio_wl32(pb, ico->images[i].size);
+        avio_wl32(pb, ico->images[i].offset);
+    }
+
+    av_freep(&ico->images);
+
+    return 0;
+}
+
+AVOutputFormat ff_ico_muxer = {
+    .name           = "ico",
+    .long_name      = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
+    .priv_data_size = sizeof(IcoMuxContext),
+    .mime_type      = "image/vnd.microsoft.icon",
+    .extensions     = "ico",
+    .audio_codec    = CODEC_ID_NONE,
+    .video_codec    = CODEC_ID_BMP,
+    .write_header   = ico_write_header,
+    .write_packet   = ico_write_packet,
+    .write_trailer  = ico_write_trailer,
+    .flags          = AVFMT_NOTIMESTAMPS,
+};