demux_lavf, ad_lavc, vd_lavc: pass codec header data directly

Instead of putting codec header data into WAVEFORMATEX and
BITMAPINFOHEADER, pass it directly via AVCodecContext. To do this, we
add mp_copy_lav_codec_headers(), which copies the codec header data
from one AVCodecContext to another (originally, the plan was to use
avcodec_copy_context() for this, but it looks like this would turn
decoder initialization into an even worse mess).

Get rid of the silly CodecID <-> codec_tag mapping. This was originally
needed for codecs.conf: codec tags were used to identify codecs, but
libavformat didn't always return useful codec tags (different file
formats can have different, overlapping tag numbers). Since we don't
go through WAVEFORMATEX etc. and pass all header data directly via
AVCodecContext, we can be absolutely sure that the codec tag mapping is
not needed anymore.

Note that this also destroys the "standard" MPlayer method of exporting
codec header data. WAVEFORMATEX and BITMAPINFOHEADER made sure that
other non-libavcodec decoders could be initialized. However, all these
decoders have been removed, so this is just cruft full of old hacks that
are not needed anymore. There's still ad_spdif and ad_mpg123, bu neither
of these need codec header data. Should we ever add non-libavcodec
decoders, better data structures without the past hacks could be added
to export the headers.

1 files changed, 12 insertions, 78 deletions

diff --git a/demux/demux_lavf.c b/demux/demux_lavf.c
index 7ae063777a..ca81a45f84 100644
--- a/demux/demux_lavf.c
+++ b/demux/demux_lavf.c
@@ -46,8 +46,6 @@
 #include "stheader.h"
 #include "core/m_option.h"
 
-#include "mp_taglists.h"
-
 #define INITIAL_PROBE_SIZE STREAM_BUFFER_SIZE
 #define PROBE_BUF_SIZE (2 * 1024 * 1024)
 
@@ -329,100 +327,36 @@ static void handle_stream(demuxer_t *demuxer, AVFormatContext *avfc, int i)
     AVStream *st = avfc->streams[i];
     AVCodecContext *codec = st->codec;
     struct sh_stream *sh = NULL;
-    // Work around collisions resulting from the hacks changing codec_tag.
-    int lavf_codec_tag = codec->codec_tag;
-    // Don't use native MPEG codec tag values with our generic tag tables.
-    // May contain for example value 3 for MP3, which we'd map to PCM audio.
-    if (matches_avinputformat_name(priv, "mpeg") ||
-            matches_avinputformat_name(priv, "mpegts"))
-        codec->codec_tag = 0;
-    int override_tag = mp_taglist_override(codec->codec_id);
-    // For some formats (like PCM) always trust CODEC_ID_* more than codec_tag
-    if (override_tag)
-        codec->codec_tag = override_tag;
-
-    const char *mp_codec = mp_codec_from_av_codec_id(codec->codec_id);
 
     switch (codec->codec_type) {
     case AVMEDIA_TYPE_AUDIO: {
-        WAVEFORMATEX *wf;
-        sh_audio_t *sh_audio;
-        sh_audio = new_sh_audio_aid(demuxer, i, priv->audio_streams);
+        sh_audio_t *sh_audio = new_sh_audio_aid(demuxer, i, priv->audio_streams);
         if (!sh_audio)
             break;
         sh = sh_audio->gsh;
         priv->astreams[priv->audio_streams] = i;
-        wf = calloc(sizeof(*wf) + codec->extradata_size, 1);
-        // mp4a tag is used for all mp4 files no matter what they actually contain
-        if (codec->codec_tag == MKTAG('m', 'p', '4', 'a'))
-            codec->codec_tag = 0;
-        if (!codec->codec_tag)
-            codec->codec_tag = mp_taglist_audio(codec->codec_id);
-        if (!codec->codec_tag)
-            codec->codec_tag = -1;
-        wf->wFormatTag = codec->codec_tag;
-        wf->nChannels = codec->channels;
-        wf->nSamplesPerSec = codec->sample_rate;
-        wf->nAvgBytesPerSec = codec->bit_rate / 8;
-        wf->nBlockAlign = codec->block_align;
-        wf->wBitsPerSample = codec->bits_per_coded_sample;
-        wf->cbSize = codec->extradata_size;
-        if (codec->extradata_size)
-            memcpy(wf + 1, codec->extradata, codec->extradata_size);
-        sh_audio->wf = wf;
         sh_audio->ds = demuxer->audio;
         sh_audio->format = codec->codec_tag;
+
+        // probably unneeded
         sh_audio->channels = codec->channels;
         sh_audio->samplerate = codec->sample_rate;
         sh_audio->i_bps = codec->bit_rate / 8;
-        switch (codec->codec_id) {
-        case CODEC_ID_PCM_ALAW:
-            sh_audio->format = 0x6;
-            break;
-        case CODEC_ID_PCM_MULAW:
-            sh_audio->format = 0x7;
-            break;
-        }
+
         st->discard = AVDISCARD_ALL;
         priv->audio_streams++;
         break;
     }
     case AVMEDIA_TYPE_VIDEO: {
-        sh_video_t *sh_video;
-        BITMAPINFOHEADER *bih;
-        sh_video = new_sh_video_vid(demuxer, i, priv->video_streams);
+        sh_video_t *sh_video = new_sh_video_vid(demuxer, i, priv->video_streams);
         if (!sh_video)
             break;
         sh = sh_video->gsh;
         priv->vstreams[priv->video_streams] = i;
         if (st->disposition & AV_DISPOSITION_ATTACHED_PIC)
             sh_video->gsh->attached_picture = true;
-        bih = calloc(sizeof(*bih) + codec->extradata_size, 1);
-
-        if (codec->codec_id == CODEC_ID_RAWVIDEO) {
-            switch (codec->pix_fmt) {
-            case PIX_FMT_RGB24:
-                codec->codec_tag = MKTAG(24, 'B', 'G', 'R');
-            case PIX_FMT_BGR24:
-                codec->codec_tag = MKTAG(24, 'R', 'G', 'B');
-            }
-            if (!codec->codec_tag)
-                codec->codec_tag = avcodec_pix_fmt_to_codec_tag(codec->pix_fmt);
-        } else if (!codec->codec_tag) {
-            codec->codec_tag = mp_taglist_video(codec->codec_id);
-            /* 0 might mean either unset or rawvideo; if codec_id
-             * was not RAWVIDEO assume it's unset
-             */
-            if (!codec->codec_tag)
-                codec->codec_tag = -1;
-        }
-        bih->biSize = sizeof(*bih) + codec->extradata_size;
-        bih->biWidth = codec->width;
-        bih->biHeight = codec->height;
-        bih->biBitCount = codec->bits_per_coded_sample;
-        bih->biSizeImage = bih->biWidth * bih->biHeight * bih->biBitCount / 8;
-        bih->biCompression = codec->codec_tag;
-        sh_video->bih = bih;
+
+        sh_video->format = codec->codec_tag;
         sh_video->disp_w = codec->width;
         sh_video->disp_h = codec->height;
         /* Try to make up some frame rate value, even if it's not reliable.
@@ -441,7 +375,6 @@ static void handle_stream(demuxer_t *demuxer, AVFormatContext *avfc, int i)
                               st->codec->ticks_per_frame);
         sh_video->fps = fps;
         sh_video->frametime = 1 / fps;
-        sh_video->format = bih->biCompression;
         if (st->sample_aspect_ratio.num)
             sh_video->aspect = codec->width  * st->sample_aspect_ratio.num
                     / (float)(codec->height * st->sample_aspect_ratio.den);
@@ -455,8 +388,6 @@ static void handle_stream(demuxer_t *demuxer, AVFormatContext *avfc, int i)
                codec->height, codec->sample_aspect_ratio.den);
 
         sh_video->ds = demuxer->video;
-        if (codec->extradata_size)
-            memcpy(sh_video->bih + 1, codec->extradata, codec->extradata_size);
         if (demuxer->video->id != priv->video_streams
             && demuxer->video->id != -1)
             st->discard = AVDISCARD_ALL;
@@ -518,8 +449,11 @@ static void handle_stream(demuxer_t *demuxer, AVFormatContext *avfc, int i)
         st->discard = AVDISCARD_ALL;
     }
     if (sh) {
-        sh->codec = mp_codec;
-        sh->lavf_codec_tag = lavf_codec_tag;
+        sh->codec = mp_codec_from_av_codec_id(codec->codec_id);
+        sh->lav_headers = avcodec_alloc_context3(codec->codec);
+        assert(sh->lav_headers);
+        avcodec_copy_context(sh->lav_headers, codec);
+
         if (st->disposition & AV_DISPOSITION_DEFAULT)
             sh->default_track = 1;
         if (matches_avinputformat_name(priv, "mpeg"))